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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value Measurements, Recurring and Nonrecurring [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of assets and liabilities measured at fair value on a recurring basis</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInAccountsPayable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Accounts Payable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInAccountsPayable_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Increase (Decrease) in Accounts Payable, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInAccountsPayable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accounts payble</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_RestatementAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Revision of Prior Period [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashFlowNoncashInvestingAndFinancingActivitiesDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash Flow, Noncash Investing and Financing Activities Disclosure [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashFlowNoncashInvestingAndFinancingActivitiesDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Supplemental disclosures of non-cash investing and financing activities:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PlanNameAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Plan Name [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ResearchAndDevelopmentExpenseAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Research and Development Expense [Abstract]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_CommonStockOfHelixIssuedInThePIPEFinancing_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock Of Helix Issued In The PIPE Financing</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_CommonStockOfHelixIssuedInThePIPEFinancing_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Common Stock Of Helix Issued In The PIPE Financing</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquityAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityCurrentReportingStatus_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Current Reporting Status</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInProfessionalFeePayable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Professional Fee Payable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInProfessionalFeePayable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accrued professional services</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingExpensesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Expenses [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingExpensesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Operating expenses:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueInputsLevel2Member_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Level 2</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueInputsLevel2Member_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value, Inputs, Level 2 [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_UnpaidPropertyAndEquipmentIncludedInOtherAccruedLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Unpaid Property and Equipment Included in Other Accrued Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_UnpaidPropertyAndEquipmentIncludedInOtherAccruedLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Unpaid Property and Equipment Included in Other Accrued Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_UnpaidPropertyAndEquipmentIncludedInOtherAccruedLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Unpaid property and equipment included in accounts payable and other accrued liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_UnvestedRestrictedStockUnitsOfCommonStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Unvested Restricted Stock Units of Common Stock [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_UnvestedRestrictedStockUnitsOfCommonStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Unvested Restricted Stock Units of Common Stock [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_UnvestedRestrictedStockUnitsOfCommonStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Unvested RSU's of common stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommitmentsAndContingenciesDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Commitments and Contingencies Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommitmentsAndContingenciesDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Commitments and Contingencies</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesAuthorized_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock, Shares Authorized</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesAuthorized_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common stock, shares authorized</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OptionIndexedToIssuersEquityTypeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Option Indexed to Issuer's Equity, Type [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareBasicAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Earnings Per Share, Basic [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_TransactionCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Transaction costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_TransactionCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Represent amount of transaction costs.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_TransactionCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Transaction Costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentFiscalPeriodFocus_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Fiscal Period Focus</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityShellCompany_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Shell Company</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherAccruedLiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other accrued liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherAccruedLiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Accrued Liabilities, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_FacilitiesAndOtherExpensesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Facilities And Other Expenses [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_FacilitiesAndOtherExpensesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Facilities And Other Expenses [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsForOtherOperatingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash Payment to an Executive Contingent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsForOtherOperatingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payment for Other Operating Activity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SegmentReportingPolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Segment Reporting, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SegmentReportingPolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Segments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsAtCarryingValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash and Cash Equivalent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsAtCarryingValue_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Cash and Cash Equivalent, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsAtCarryingValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash and cash equivalents</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ResearchAndDevelopmentArrangementContractToPerformForOthersTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Research and Development Arrangement, Contract to Perform for Others [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ResearchAndDevelopmentArrangementContractToPerformForOthersTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Research and Development Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NotesPayableCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Notes Payable, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NotesPayableCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Payables to related parties</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_CashUnderwritingFee_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash underwriting fee</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_CashUnderwritingFee_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Represent the amount of cash underwriting fee.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_CashUnderwritingFee_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash Underwriting Fee</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesIssued_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Common stock, shares issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesIssued_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock, Shares, Issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesIssued_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common stock, shares issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseDescription_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Description</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseDescription_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Lessee Operating Lease Description</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Asset Class [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statement [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_RedeemableConvertiblePreferredStockOnAnAsConvertedIntoCommonStockBasisMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Redeemable Convertible Preferred Stock On An As Converted Into Common Stock Basis [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_RedeemableConvertiblePreferredStockOnAnAsConvertedIntoCommonStockBasisMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Redeemable Convertible Preferred Stock On An As Converted Into Common Stock Basis [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_RedeemableConvertiblePreferredStockOnAnAsConvertedIntoCommonStockBasisMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Redeemable convertible preferred stock on an as-converted into common stock basis</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestrictedCashNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Restricted Cash, Noncurrent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestrictedCashNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Restricted cash</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Right-of-use asset recognized in exchange for operating lease liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Right-of-Use Asset Obtained in Exchange for Operating Lease Liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInPrepaidExpense_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Prepaid expense and other currents assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInPrepaidExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Prepaid Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">weighted-average grant granted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_AccruedInterestOnMarketableSecurities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accrued interest in marketable securities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_AccruedInterestOnMarketableSecurities_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Amount on accrued Interest on marketable securities.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_AccruedInterestOnMarketableSecurities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accrued Interest On Marketable Securities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardPurchasePriceOfCommonStockPercent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Purchase Price of Common Stock, Percent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardPurchasePriceOfCommonStockPercent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Reduction in fair valuse percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_LeidosBiomedicalResearchLicenseAndCooperativeResearchAndDevelopmentAgreementsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Leidos Biomedical Research License And Cooperative Research And Development Agreements [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_LeidosBiomedicalResearchLicenseAndCooperativeResearchAndDevelopmentAgreementsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Leidos Biomedical Research License And Cooperative Research And Development Agreements [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_LeidosBiomedicalResearchLicenseAndCooperativeResearchAndDevelopmentAgreementsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Leidos CRADA [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statement [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessAcquisitionAcquireeDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityFilerCategory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Filer Category</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesAndStockholdersEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Liabilities and Equity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesAndStockholdersEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total liabilities, redeemable convertible preferred stock, and stockholders' equity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInEmployeeRelatedLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accrued compensation and benefits</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInEmployeeRelatedLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Employee Related Liabilities</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquireMarketableSecurities_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Purchases of marketable securities</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercisable, Weighted Average Exercise Price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Exercisable as of June 30, 2026</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_LicenseAndCollaborationAgreementsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">License And Collaboration Agreements [Abstract]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsRestrictedCashAndCashEquivalentsPolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash, Cash Equivalents, and Restricted Cash</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AllowanceForDoubtfulAccountsReceivable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Allowance for credit losses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AllowanceForDoubtfulAccountsReceivable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounts Receivable, Allowance for Credit Loss</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AllowanceForDoubtfulAccountsReceivable_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Accounts Receivable, Allowance for Credit Loss, Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AllowanceForDoubtfulAccountsReceivable_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Accounts Receivable, Allowance for Credit Loss, Beginning Balance</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_Long-TermMarketableSecuritiesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Long-Term Marketable Securities [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_Long-TermMarketableSecuritiesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Long-Term Marketable Securities</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SignificantAccountingPoliciesTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Significant Accounting Policies [Text Block]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_TransitionServicesAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Transition Services Agreement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_TransitionServicesAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Transition Services Agreement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_ShareBasedCompensationArrangementByPerformanceBasedMilestoneAwards_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share Based Compensation Arrangement By Performance Based Milestone Awards</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_ShareBasedCompensationArrangementByPerformanceBasedMilestoneAwards_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Share Based Compensation Arrangement By Performance Based Milestone Awards</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_ShareBasedCompensationArrangementByPerformanceBasedMilestoneAwards_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Performance-based milestone awards</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Granted</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Number of options granted</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Schedule of Diluted Net Loss Per Share Attributable to Common Stockholders</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DividendsPayableCurrentAndNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Dividends Payable</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareBasic_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Earnings Per Share, Basic</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareBasic_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Net loss per share attributable to common stockholders, basic</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Number</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedWeightedAverageGrantDateFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Weighted average grant date fair value, Vested</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedWeightedAverageGrantDateFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Vested, Weighted Average Grant Date Fair Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_InducementPlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Inducement Plan [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_InducementPlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">2025 Inducement Plan [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_InducementPlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">2025 Inducement Plan [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total current liabilities</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_PayrollAndPersonnelExpensesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Payroll And Personnel Expenses [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_AccruedResearchAndDevelopmentCostsCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accrued Research and Development Costs Current</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_ResearchAndCollaborationAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Research And Collaboration Agreement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_ResearchAndCollaborationAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Research And Collaboration Agreement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquityAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity, Attributable to Parent [Abstract]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntitySmallBusiness_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Small Business</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RedeemableNoncontrollingInterestEquityCarryingAmountAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Less:</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromIssuanceInitialPublicOffering_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Gross proceeds</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonClassAMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Class A [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContractWithCustomerLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Contract with Customer, Liability</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_AmendmentFlag_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Amendment Flag</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerSharePolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Net Loss per Share Attributable to Common Stockholders</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerSharePolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Earnings Per Share, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressPostalZipCode_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Address, Postal Zip Code</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net cash used in operating activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash Provided by (Used in) Operating Activity, Including Discontinued Operation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInOperatingLeaseLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Operating Lease Liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInOperatingLeaseLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Operating lease liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentRedemptionPricePercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt Instrument, Redemption Price, Percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentRedemptionPricePercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Redemption Price, Percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_InterestToPayDissolutionExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Interest to pay dissolution expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_InterestToPayDissolutionExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Interest to pay dissolution expenses.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_InterestToPayDissolutionExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Interest To Pay Dissolution Expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common Stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangements by Share-Based Payment Award, Options, Grants in Period, Weighted Average Exercise Price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Granted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearThree_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Liability, to be Paid, Year Three</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearThree_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2029</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessDescriptionAndAccountingPoliciesTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Description of the Business</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessDescriptionAndAccountingPoliciesTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Description and Accounting Policies [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressAddressLine1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Address, Address Line One</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueByFairValueHierarchyLevelAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value Hierarchy and NAV [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Earnings Per Share [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Income Taxes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Tax, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TemporaryEquityCarryingAmountAttributableToParent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Class A ordinary shares subject to possible redemption, 18,400,000 shares at redemption value of $10.68 and $10.46 per share as of June 30, 2025 and December 31, 2024, respectively</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TemporaryEquityCarryingAmountAttributableToParent_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Class A ordinary shares subject to possible redemption</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TemporaryEquityCarryingAmountAttributableToParent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Temporary Equity, Carrying Amount, Attributable to Parent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquityNoteRedeemablePreferredStockIssuePolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stockholders' Equity Note, Redeemable Preferred Stock, Issue, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquityNoteRedeemablePreferredStockIssuePolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Redeemable Convertible Preferred Stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsForUnderwritingExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Payment of fees and expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsForUnderwritingExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payments for Underwriting Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsForUnderwritingExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Proceeds to net of underwriting discount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseRightOfUseAsset_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Lease, Right-of-Use Asset</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseRightOfUseAsset_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Operating lease right-of-use asset</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentType_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Type</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TypeOfArrangementAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Collaborative Arrangement and Arrangement Other than Collaborative [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ArrangementsAndNonarrangementTransactionsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Collaborative Arrangement and Arrangement Other than Collaborative [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityCentralIndexKey_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Central Index Key</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityCentralIndexKey_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Central Index Key</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestrictedCashAndCashEquivalentsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Restricted Cash and Cash Equivalent [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_MinimumMaturityofInvestment_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Minimum maturity term</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_MinimumMaturityofInvestment_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">The maximum maturity term of investments, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_MinimumMaturityofInvestment_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Minimum Maturityof Investment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Period Increase (Decrease), Excluding Exchange Rate Effect, Including Discontinued Operation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net increase in cash, cash equivalents, and restricted cash</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InterestIncomeOperating_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Interest income</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InterestIncomeOperating_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Interest Income, Operating</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InterestIncomeOperating_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Interest Income, Operating, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Antidilutive securities excluded from computation of earnings per share, amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Shares Reserved for Issuance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_OfferingPriceRelatedToSeriesB_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Offering Price Related to Series B</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_OfferingPriceRelatedToSeriesB_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Offering Price Related to Series B</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_OfferingPriceRelatedToSeriesB_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Offering Price Related to Series B</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdjustmentsToAdditionalPaidInCapitalShareBasedCompensationStockOptionsRequisiteServicePeriodRecognition_lbl" xlink:role="http://www.xbrl.org/2003/role/label">APIC, Share-Based Payment Arrangement, Option, Increase for Cost Recognition</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdjustmentsToAdditionalPaidInCapitalShareBasedCompensationStockOptionsRequisiteServicePeriodRecognition_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stock-based compensation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_OtherNonCashAdjustmentsNet_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Non Cash Adjustments, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_OtherNonCashAdjustmentsNet_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Other Non Cash Adjustments, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_OtherNonCashAdjustmentsNet_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Other non cash adjustments, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockParOrStatedValuePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock, Par or Stated Value Per Share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockParOrStatedValuePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common stock, par value (in Dollars per share)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Liabilities [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_NetProceedsFromSaleOfUnits_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Net proceeds from sale of units</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_NetProceedsFromSaleOfUnits_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Net proceeds from sale of units.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_NetProceedsFromSaleOfUnits_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Net Proceeds From Sale Of Units</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Weighted Average Remaining Contractual Term (Years) , Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Securities, Available-for-Sale, Amortized Cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Debt Securities, Available-for-Sale, Amortized Cost, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Amortized Cost Basis</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_RedemptionOfHelixCommonStock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Redemption Of Helix Common Stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_RedemptionOfHelixCommonStock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Redemption Of Helix Common Stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_RedemptionOfHelixCommonStock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Redemption of Helix common stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_BridgeBioPharmaMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">BridgeBio Pharma [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_BridgeBioPharmaMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">BridgeBio Pharma [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_BridgeBioPharmaMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">BridgeBio Pharma</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_BridgeBioPharmaMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">BridgeBio Pharma</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercises in Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Number of options exercised</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Exercise of common stock options for cash</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Number of Options, Exercised</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_RestrictedCashMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Restricted cash [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_RestrictedCashMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Restricted cash [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_RestrictedCashMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Restricted cash [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_LegacyBBOTCommonStock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Legacy BBOT Common Stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_LegacyBBOTCommonStock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Legacy BBOT Common Stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_LegacyBBOTCommonStock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Legacy BBOT common stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MarketableSecurities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Marketable Securities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MarketableSecurities_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Long-term marketable securities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MarketableSecurities_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total marketable securities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MarketableSecurities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Estimated Fair Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_CurrentFiscalYearEndDate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Current Fiscal Year End Date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_ShareBasedCompensationExpenseCarveOutMethodology_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share Based Compensation Expense Carve Out Methodology</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_ShareBasedCompensationExpenseCarveOutMethodology_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Share Based Compensation Expense Carve Out Methodology</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_ShareBasedCompensationExpenseCarveOutMethodology_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Amounts recognized under the carve-out methodology</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_MilestoneLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Milestone Payment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_MilestoneLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Milestone Liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_MilestoneLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Milestone Liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentQuarterlyReport_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Quarterly Report</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Restricted Cash and Cash Equivalents [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressStateOrProvince_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Address, State or Province</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Number</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Number of Shares, Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Number of Shares, Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodValueConversionOfConvertibleSecurities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Issued During Period, Value, Conversion of Convertible Securities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodValueConversionOfConvertibleSecurities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Conversion of Series B redeemable convertible preferred stock into common stock, Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInOtherAccruedLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Other Accrued Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInOtherAccruedLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other accrued liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Preferred Stock, Shares Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Preferred Stock, Shares Outstanding, Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Preferred Stock, Shares Outstanding, Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Shares Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Preferred stock, shares outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ComprehensiveIncomeNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Comprehensive Income (Loss), Net of Tax, Attributable to Parent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ComprehensiveIncomeNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Comprehensive loss</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Gain, before Tax</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Gross Unrealized Gains</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ResearchAndDevelopmentExpensePolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Research and Development Expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ResearchAndDevelopmentExpensePolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Research and Development Expense, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockCapitalSharesReservedForFutureIssuance_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock, Capital Shares Reserved for Future Issuance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockCapitalSharesReservedForFutureIssuance_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common Stock Shares Reserved</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConversionOfStockSharesConverted1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Conversion of Stock, Shares Converted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConversionOfStockSharesConverted1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Outstanding and unexercised common stock converted into aggregate common stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MarketableSecuritiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Marketable Securities, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MarketableSecuritiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Short-term marketable securities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MarketableSecuritiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Estimated Fair Value, Short Term</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Stock-based compensation expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProfessionalFees_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Professional Fees</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProfessionalFees_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Professional Fees</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Issued During Period, Value, Stock Options Exercised</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Exercise of common stock options for cash (Amount)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ComprehensiveIncomePolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Comprehensive Income, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ComprehensiveIncomePolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other Comprehensive Income or Loss</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CollaborativeArrangementDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Collaborative Arrangement Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CollaborativeArrangementDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">In-Licensing and Collaboration Agreements</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromSaleAndMaturityOfMarketableSecurities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds from Sale and Maturity of Marketable Securities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromSaleAndMaturityOfMarketableSecurities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Maturities and sales of marketable securities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MarketableSecuritiesPolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Marketable Securities, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MarketableSecuritiesPolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Marketable Securities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_PublicSharesPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Redeem public shares, percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_PublicSharesPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Redeem public shares, percentage.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_PublicSharesPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Public Shares Percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_Short-TermMarketableSecuritiesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Short-Term Marketable Securities [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_Short-TermMarketableSecuritiesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Short-Term Marketable Securities [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_Short-TermMarketableSecuritiesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Short-Term Marketable Securities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherAssetsNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Assets, Noncurrent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherAssetsNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other non-current assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromIssuanceOfConvertiblePreferredStock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds from Issuance of Convertible Preferred Stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromIssuanceOfConvertiblePreferredStock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Issuance of Series B redeemable convertible preferred stock, net of issuance costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Antidilutive Securities [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_ScheduleOfClassAOrdinarySharesSubjectToRedemptionReflectedAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule Of Class AOrdinary Shares Subject To Redemption Reflected [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_MilestonePaymentsUnderInLicensingAgreementsPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Milestone Payments Under In Licensing Agreements [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_MilestonePaymentsUnderInLicensingAgreementsPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Milestone Payments Under In Licensing Agreements [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_MilestonePaymentsUnderInLicensingAgreementsPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Milestone Payments Under In-Licensing Agreements</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RelatedPartyTransactionAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Related Party Transaction [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedOtherComprehensiveIncomeMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">AOCI Attributable to Parent [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedOtherComprehensiveIncomeMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accumulated Other Comprehensive Income</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash and Cash Equivalents [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_ParticipationRightLiabilityPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Participation Right Liability [Policy Text Block ]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_ParticipationRightLiabilityPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Participation Right Liability [Policy Text Block ]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_ParticipationRightLiabilityPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Participation Right Liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TemporaryEquityCarryingAmountIncludingPortionAttributableToNoncontrollingInterestsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Plus:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TemporaryEquityCarryingAmountIncludingPortionAttributableToNoncontrollingInterestsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Temporary Equity, Including Noncontrolling Interest [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_BusinessCombinationMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Business Combination [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_BusinessCombinationMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Preferred Stock, Value, Issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Preference stock, value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockValue_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Carrying Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_WorkingCapitalLoan_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Working capital loans</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_WorkingCapitalLoan_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Working capital loans (in Dollars)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_WorkingCapitalLoan_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Working capital loan.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_WorkingCapitalLoan_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Working Capital Loan</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_MinimumMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Minimum [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_MinimumMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Minimum</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_MinimumMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Minimum [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Weighted Average Grant Date Fair Value, Granted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FinancialInstrumentAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Financial Instrument [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsCurrentAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Assets, Current [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsCurrentAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Current assets:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_RCALicenseGrantMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">RCA License Grant [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_RCALicenseGrantMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">RCA License Grant [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_RCALicenseGrantMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">RCA License Grant [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonClassBMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Class B Ordinary Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonClassBMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Class B</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonClassBMember_lbl" xlink:role="http://www.xbrl.org/2009/role/netLabel">Class B [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonClassBMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Class B Ordinary Shares [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueInputsLevel3Member_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value, Inputs, Level 3 [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueInputsLevel3Member_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Level 3</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RepaymentsOfOtherDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Repayments of Other Debt</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RepaymentsOfOtherDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Performance Cash Bonus Payment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SegmentReportingAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Segment Information [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationsPolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination [Policy Text Block]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_StockOptionAndIncentivePlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Stock Option and Incentive Plan [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_StockOptionAndIncentivePlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stock Option And Incentive Plan [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RelatedPartyTransactionsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Related Party Transactions [Abstract]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_LegacyBBOTCommonStockOption_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Legacy BBOT Common Stock Option</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_LegacyBBOTCommonStockOption_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Legacy BBOT common stock option</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Weighted Average Grant Date Fair Value, Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Weighted Average Grant Date Fair Value, Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GeneralAndAdministrativeExpenseMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">General and administrative</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_RelatedPartyIncomeAndExpensesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Related Party Income and Expenses [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_RelatedPartyIncomeAndExpensesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Related Party Income and Expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MarketableSecuritiesNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Marketable Securities, Noncurrent</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_CommonStockOptionsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Common Stock Options [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_CommonStockOptionsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common Stock Options [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_ProbabilityWeightedExpectedReturnMethodSeriesB_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Probability Weighted Expected Return Method Series B</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_ProbabilityWeightedExpectedReturnMethodSeriesB_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Probability Weighted Expected Return Method Series B</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_ProbabilityWeightedExpectedReturnMethodSeriesB_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Probability-Weighted Expected Return Method</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Weighted-average shares outstanding basic</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Weighted Average Number of Shares Outstanding, Basic</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Weighted-average number of shares used in computing net loss per share attributable to common stockholders, basic</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfRestrictedCashAndCashEquivalentsTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Restrictions on Cash and Cash Equivalents [Table]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_TrustAccountPublicPricePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Represent the amount of trust account public price.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_TrustAccountPublicPricePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Trust Account Public Price Per Share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercisable, Intrinsic Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Exercisable as of June 30, 2026</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardPlanModificationIncrementalCompensationCost_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Incremental stock-based compensation expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SeriesBMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Series B [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SeriesBMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Series B</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Share-Based Compensation Arrangements by Share-Based Payment Award [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromIssuanceOfPrivatePlacement_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Aggregate private placement</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Cash_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Cash_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Balance</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_InvestmentCategoryDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Investment Category [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_InvestmentCategoryDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Investment Category [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BasisOfAccountingPolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Basis of Accounting, Policy [Policy Text Block]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_DeferredDe-SPACTransactionCostsIncludedInAccruedProfessionalServicesAndOtherAccruedLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Deferred De-SPAC Transaction Costs Included in Accrued Professional Services and Other Accrued Liabilities</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_ParticipationRightLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Participation Right Liability, Beginning Balance</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_SharesReservedForIssuanceUnderTheInducementPlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Shares reserved for issuance under the inducement plan [Member]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_SharesReservedForIssuanceUnderTheInducementPlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Shares available for issuance under the inducement plan</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PlanNameDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Plan Name [Domain]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_ScheduleOfResearchAndDevelopmentExpensesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Schedule of Research and Development Expenses [Table Text Block ]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfShareBasedPaymentAwardEmployeeStockPurchasePlanValuationAssumptionsTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Share-Based Payment Award, Employee Stock Purchase Plan, Valuation Assumptions [Table Text Block]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_SharesReservedForIssuanceUnderStockOptionAndIncentivePlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Shares reserved for issuance under stock option and incentive plan [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_SharesReservedForIssuanceUnderStockOptionAndIncentivePlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Shares reserved for issuance under stock option and incentive plan</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CertificatesOfDepositMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Certificates of Deposit [Member]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, Plant and Equipment, Policy [Policy Text Block]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressCityOrTown_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Address, City or Town</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_SecurityExchangeName_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Security Exchange Name</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TemporaryEquityTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Class A Ordinary Shares Subject to Redemption Reflected</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Liability for Unpaid Claims and Claims Adjustment Expense, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Liability for Unpaid Claims and Claims Adjustment Expense, Net, Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Liability for Unpaid Claims and Claims Adjustment Expense, Net, Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Milestone Payment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_PIPEFinancingAndDe-SPACTransactionTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">PIPE Financing and de-SPAC Transaction [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_PIPEFinancingAndDe-SPACTransactionTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">PIPE Financing and de-SPAC Transaction [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_PIPEFinancingAndDe-SPACTransactionTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">PIPE Financing and de-SPAC Transaction</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AuctionMarketPreferredSecuritiesStockSeriesAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Auction Market Preferred Securities, Stock Series [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_CounterpartyNameAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Counterparty Name [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_FairValueMeasurementsTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value Measurements [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_FairValueMeasurementsTable_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Fair Value Measurements [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedOptionsForfeitedWeightedAverageGrantDateFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Nonvested Options Forfeited, Weighted Average Grant Date Fair Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedOptionsForfeitedWeightedAverageGrantDateFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Weighted average grant date fair value, Forfeited</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AntidilutiveSecuritiesNameDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Antidilutive Securities, Name [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_HelixCommonStockSubjectToRedemptionPriorToTheClosing_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Helix Common Stock Subject To Redemption Prior To The Closing</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_HelixCommonStockSubjectToRedemptionPriorToTheClosing_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Helix Common Stock Subject To Redemption Prior To The Closing</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_HelixCommonStockSubjectToRedemptionPriorToTheClosing_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Helix common stock subject to redemption prior to the Closing</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Continuing Operation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Cash, cash equivalents, and restricted cash at beginning of period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Cash, cash equivalents, and restricted cash at end of period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total cash, cash equivalents, and restricted cash</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Table]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentPeriodEndDate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Period End Date</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Exercisable as of June 30, 2026</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementOfFinancialPositionAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statement of Financial Position [Abstract]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InProcessResearchAndDevelopmentPolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/label">In Process Research and Development, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InProcessResearchAndDevelopmentPolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accrued Research and Development Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_ScheduleOfSharesReservedForIssuanceTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Shares Reserved for Issuance [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_ScheduleOfSharesReservedForIssuanceTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Schedule of Shares Reserved for Issuance [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_ScheduleOfSharesReservedForIssuanceTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Shares Reserved for Issuance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Liabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Liabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Total liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Liabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Financial Instruments [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CapitalUnitsAuthorized_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Capital Units, Authorized</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CapitalUnitsAuthorized_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Authorized Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquityMethodInvestmentsPolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity Method Investments [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquityMethodInvestmentsPolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Equity Method Investment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearTwo_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Liability, to be Paid, Year Two</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearTwo_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2028</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestrictedCashAndCashEquivalentsItemsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Restricted Cash and Cash Equivalent Item [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestrictedCash_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Restricted Cash</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestrictedCash_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Restricted cash</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestrictedCash_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Restricted Cash, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInParticipationLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Change in fair value of participation right liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInParticipationLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Participation Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInParticipationLiabilities_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Change in fair value of participation right liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Weighted-average shares outstanding diluted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Weighted Average Number of Shares Outstanding, Diluted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Weighted-average number of shares used in computing net loss per share attributable to common stockholders, diluted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInDueFromRelatedParties_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Due from Related Parties</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInDueFromRelatedParties_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Increase (Decrease) in Due from Related Parties, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInDueFromRelatedParties_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Balances due to and from related parties</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityFileNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity File Number</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_CoverAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cover [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_RemainsDilutedOutstandingCapitalization_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Remains Diluted Outstanding Capitalization</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_RemainsDilutedOutstandingCapitalization_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Remains Diluted Outstanding Capitalization</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_RemainsDilutedOutstandingCapitalization_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Remains Diluted Outstanding Capitalization</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_DilutedOutstandingCapitalization_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Diluted Outstanding Capitalization</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_DilutedOutstandingCapitalization_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Diluted Outstanding Capitalization</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_DilutedOutstandingCapitalization_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Representing Diluted Outstanding Capitalization</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PrepaidExpenseAndOtherAssetsCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Prepaid Expense and Other Assets, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PrepaidExpenseAndOtherAssetsCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Prepaid expense and other current assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PrepaidExpenseAndOtherAssetsCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total prepaid expenses and other current assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Forfeited in Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Number of Shares, Forfeited and cancelled</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DirectTaxesAndLicensesCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">License Maintenance Fees</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DirectTaxesAndLicensesCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cost, Direct Tax and License</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NumberOfOperatingSegments_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Operating segment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NumberOfOperatingSegments_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Number of Operating Segments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SaleOfStockNameOfTransactionDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Sale of Stock [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProfessionalAndContractServicesExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Deferred de-SPAC transaction costs included in accrued professional services and other accrued liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProfessionalAndContractServicesExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Professional and Contract Services Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SegmentReportingDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">SEGMENT INFORMATION</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SegmentReportingDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Segment Reporting Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_AllocatedOperatingExpensesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Allocated Operating Expenses [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_AllocatedOperatingExpensesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Allocated Operating Expenses [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_AllocatedOperatingExpensesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Allocated Operating Expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GeneralAndAdministrativeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">General and Administrative Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GeneralAndAdministrativeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">General and Administrative Expense, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GeneralAndAdministrativeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">General and administrative expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GeneralAndAdministrativeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">General and administrative</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SeriesBPreferredStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Series B Preferred Stock [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SeriesBPreferredStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Series B Preferred Stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SeriesBPreferredStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Series B [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockConvertibleConversionPrice_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Original Issue Price Per Share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockConvertibleConversionPrice_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Preferred Stock, Convertible, Conversion Price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedNumberOfShares_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Vested, Number of Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedNumberOfShares_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Number of options vested</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedNumberOfShares_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Vested and released</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_SharesPurchasePercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Shares Purchase Percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_SharesPurchasePercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Shares Purchase Percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_SharesPurchasePercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Shares Purchase Percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Forfeitures and Expirations in Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Forfeitures and Expirations in Period, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Forfeited and cancelled</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriod_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Forfeited and cancelled</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesOther_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Issued During Period, Shares, Other</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesOther_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stock Issued During Period Shares Other</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MarketableSecuritiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Marketable Securities [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MarketableSecuritiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Marketable securities:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedWeightedAverageGrantDateFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Option, Nonvested, Weighted Average Exercise Price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedWeightedAverageGrantDateFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Share-Based Compensation Arrangement by Share-Based Payment Award, Option, Nonvested, Weighted Average Exercise Price, Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedWeightedAverageGrantDateFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Share-Based Compensation Arrangement by Share-Based Payment Award, Option, Nonvested, Weighted Average Exercise Price, Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedWeightedAverageGrantDateFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">unvested common stock options</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">New Accounting Pronouncements, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Recently Issued Accounting Pronouncements</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityMaturityTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of amortization of Company's lease liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityMaturityTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Liability, to be Paid, Maturity [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesConversionOfConvertibleSecurities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Issued During Period, Shares, Conversion of Convertible Securities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesConversionOfConvertibleSecurities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Conversion of Series B redeemable convertible preferred stock into common stock, Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_ResearchAndDevelopmentTrialsAndConsumablesExpenseMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Research And Development Trials And Consumables Expense [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_ResearchAndDevelopmentTrialsAndConsumablesExpenseMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Research And Development Trials And Consumables Expense [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentOfFinancingAndStockIssuanceCosts_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel">Payment of deferred transaction costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentOfFinancingAndStockIssuanceCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payment of Financing and Stock Issuance Costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentOfFinancingAndStockIssuanceCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Payment of Financing and Stock Issuance Costs, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MandatorilyRedeemablePreferredStockFairValueDisclosure_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Redeemable convertible preferred stock included the fair value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MandatorilyRedeemablePreferredStockFairValueDisclosure_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Mandatorily Redeemable Preferred Stock, Fair Value Disclosure</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_TotalCommonStockIssuedAndOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Total Common Stock Issued And Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_TotalCommonStockIssuedAndOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Total Common Stock Issued And Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_TotalCommonStockIssuedAndOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Total common stock issued and outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_TotalCommonStockIssuedAndOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total common stock issued and outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Depreciation_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Depreciation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Depreciation_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Depreciation, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Depreciation_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Depreciation of property and equipment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_PercentageofRedemptioninConnectionWithInitialPublicShares_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Percentage of redeem public shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_PercentageofRedemptioninConnectionWithInitialPublicShares_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Percentage of redemption in connection with initial public shares.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_PercentageofRedemptioninConnectionWithInitialPublicShares_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Percentageof Redemptionin Connection With Initial Public Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_UnderwritingDiscounts_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Underwriting discounts</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_UnderwritingDiscounts_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Represents the value of underwriting discounts.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_UnderwritingDiscounts_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Underwriting Discounts</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_InitialPublicOfferingPricePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Price per share (in Dollars per share)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_InitialPublicOfferingPricePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Initial Public Offering price per Share.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_InitialPublicOfferingPricePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Initial Public Offering Price Per Share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseTermOfContract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Term of Contract</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseTermOfContract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Lease Term</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock, Shares, Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common shares, shares outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Common Stock, Shares, Outstanding, Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Common Stock, Shares, Outstanding, Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Total common stock outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiabilityCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Lease, Liability, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiabilityCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Operating lease liability, current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Description of Organization and Business Operations [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_EmployeeStockPurchasePlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Employee Stock Purchase Plan [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_EmployeeStockPurchasePlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Employee Stock Purchase Plan [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_EmployeeStockPurchasePlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Employee Stock Purchase Plan [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentTransitionReport_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Transition Report</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total operating expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ResearchAndDevelopmentExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Research and Development Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ResearchAndDevelopmentExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total research and development</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ResearchAndDevelopmentExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Research and development</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ResearchAndDevelopmentExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Research and development expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetImpairmentCharges_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Asset Impairment Charges</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetImpairmentCharges_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Asset Impairment Charges, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetImpairmentCharges_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Impairment charges</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CostOfRevenue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cost of Revenue</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CostOfRevenue_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Cost of Revenue, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CostOfRevenue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cost of Revenue</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeasesTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Leases [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeasesTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Leases</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementOfCashFlowsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statement of Cash Flows [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_SharesIssuableUnderTheParticipationRightMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Shares issuable under the participation right</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_SharesIssuableUnderTheParticipationRightMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Shares Issuable Under The Participation Right [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_SharesIssuableUnderTheParticipationRightMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Shares Issuable Under The Participation Right [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfShareBasedCompensationStockOptionsActivityTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement, Option, Activity [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfShareBasedCompensationStockOptionsActivityTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of common stock options outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockLiquidationPreferenceValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Preferred Stock, Liquidation Preference, Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockLiquidationPreferenceValue_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Aggregate Liquidation Preference</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockLiquidationPreferenceValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Preferred stock, liquidation preference, value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquityNoteDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquityNoteDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Redeemable Convertible Preferred Stock and Stockholders' Deficit</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Earnings Per Share [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Net Loss Per Share Attributable to Common Stockholders</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TemporaryEquityLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Class A Ordinary Shares Subject to Redemption Reflected [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfShareBasedCompensationRestrictedStockUnitsAwardActivityTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Activity under the 2025 Plan with respect to the Company's RSUs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfShareBasedCompensationRestrictedStockUnitsAwardActivityTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement, Restricted Stock Unit, Activity [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetIncomeLoss_lbl" xlink:role="http://www.xbrl.org/2009/role/netLabel">Net loss</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetIncomeLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Net loss</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetIncomeLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net loss</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetIncomeLoss_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Net losses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Intrinsic Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockConvertibleSharesIssuable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Preferred Stock, Convertible, Shares Issuable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockConvertibleSharesIssuable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Preferred Stock Convertible Shares Issuable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Dividend Rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Expected dividends</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_TrustAccountDueToReductionPrice_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Reduction price (in Dollars per share)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_TrustAccountDueToReductionPrice_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Represent the per share amount of trust account due to reduction price.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_TrustAccountDueToReductionPrice_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Trust Account Due To Reduction Price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubstantialDoubtAboutGoingConcernTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Substantial Doubt about Going Concern [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubstantialDoubtAboutGoingConcernTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Liquidity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">ASSETS</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Assets [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Risk-free interest rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Risk Free Interest Rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_IntrinsicValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Intrinsic Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_IntrinsicValue_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Intrinsic Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_IntrinsicValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Intrinsic value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_SharesReservedForIssuance_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Shares Reserved For Issuance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_SharesReservedForIssuance_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Shares Reserved For Issuance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_SharesReservedForIssuance_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Shares reserved for issuance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentFiscalYearFocus_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Fiscal Year Focus</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash Provided by (Used in) Investing Activity, Including Discontinued Operation [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Investing activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsPayableCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accounts payable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsPayableCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounts Payable, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsPayableCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Accounts Payable, Current, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ResearchAndDevelopmentExpenseMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Research and Development Expense [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ResearchAndDevelopmentExpenseMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Research and development</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInOtherNoncurrentAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Other Noncurrent Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInOtherNoncurrentAssets_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Other non-current assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_RestatementDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Revision of Prior Period [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueMeasurementPolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value Measurement, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueMeasurementPolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair Value Measurements</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromStockOptionsExercised_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds from Stock Options Exercised</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromStockOptionsExercised_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Exercise of common stock options for cash</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueDisclosuresAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value Measurements [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommitmentsAndContingenciesDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Commitments and Contingencies Disclosure [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Liability, to be Paid, Year One</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2027</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromLicenseFeesReceived_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Sublicensing Income</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromLicenseFeesReceived_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds from License Fees Received</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SaleOfStockConsiderationReceivedOnTransaction_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Purchase aggregate value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SaleOfStockConsiderationReceivedOnTransaction_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Sale of Stock, Consideration Received on Transaction</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_IssuanceOfSeriesBRedeemableConvertiblePreferredStockForCashConsiderationAndSettlementOfParticipationRightLiabilityShare_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Issuance Of Series B Redeemable Convertible Preferred Stock For Cash Consideration And Settlement Of Participation Right Liability Share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_IssuanceOfSeriesBRedeemableConvertiblePreferredStockForCashConsiderationAndSettlementOfParticipationRightLiabilityShare_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Issuance of Series B Redeemable Convertible Preferred Stock for Cash Consideration and Settlement Of Participation Right Liability Share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_IssuanceOfSeriesBRedeemableConvertiblePreferredStockForCashConsiderationAndSettlementOfParticipationRightLiabilityShare_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Issuance of Series B redeemable convertible preferred stock for cash consideration and settlement of participation right liability, Share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_NoPerformanceMilestoneAwards_lbl" xlink:role="http://www.xbrl.org/2003/role/label">No Performance Milestone Awards</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_NoPerformanceMilestoneAwards_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">No Performance Milestone Awards</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_NoPerformanceMilestoneAwards_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">No performance milestone awards</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_WorkingCapitalDeficit_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Working capital deficit</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_WorkingCapitalDeficit_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">The amount of working capital deficit.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_WorkingCapitalDeficit_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Working Capital Deficit</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsFairValueDisclosure_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Assets, Fair Value Disclosure</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsFairValueDisclosure_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Assets, Fair Value Disclosure, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsFairValueDisclosure_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Total assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsidiarySaleOfStockAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Sale of Stock [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_SeriesSeedMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Series Seed [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_SeriesSeedMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Series Seed [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_SeriesSeedMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Series Seed [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_HelixCommonStockHeldByTheSponsor_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Helix common stock held by the Sponsor</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_HelixCommonStockHeldByTheSponsor_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Helix Common Stock Held By The Sponsor</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_HelixCommonStockHeldByTheSponsor_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Helix Common Stock Held By The Sponsor</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_ShareBasedCompensationArrangementByShareBasedPaymentAwardPerformanceBaseAwardsExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share Based Compensation Arrangement By Share Based Payment Award Performance Base Awards Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_ShareBasedCompensationArrangementByShareBasedPaymentAwardPerformanceBaseAwardsExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Share Based Compensation Arrangement By Share Based Payment Award Performance Base Awards Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_ShareBasedCompensationArrangementByShareBasedPaymentAwardPerformanceBaseAwardsExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Performance-based milestone awards</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInInvestingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash Provided by (Used in) Investing Activity, Including Discontinued Operation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInInvestingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net cash (used in) provided by investing activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PrivatePlacementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Private Placement Shares [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PrivatePlacementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Private Placement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PrivatePlacementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Private Placement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_DeferredDe-SPACTransactionCostsPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred de-SPAC Transaction Costs [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_DeferredDe-SPACTransactionCostsPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Deferred de-SPAC Transaction Costs [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_DeferredDe-SPACTransactionCostsPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Deferred de-SPAC Transaction Costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_Security12bTitle_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Title of 12(b) Security</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_QualifyingLiquidityEventProbability_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Probability of a qualifying liquidity event</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_QualifyingLiquidityEventProbability_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Qualifying Liquidity Event Probability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_QualifyingLiquidityEventProbability_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Qualifying Liquidity Event Probability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">weighted-average grant-date fair vested and forfeiture</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangements by Share-Based Payment Award, Options, Forfeitures in Period, Weighted Average Exercise Price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Weighted Average Grant Date Fair Value, Forfeited and cancelled</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MoneyMarketFundsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Money market funds</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MoneyMarketFundsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Money Market Funds [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestrictedInvestmentsPercentOfNetAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Percentage of restricted redeeming shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestrictedInvestmentsPercentOfNetAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Restricted Investments, Percent of Net Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RelatedPartyDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Related and Nonrelated Parties [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_DescriptionofOrganizationandBusinessOperationsDetailsTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Description of Organization and Business Operations (Details) [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Tax Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Income Taxes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtSecuritiesAvailableForSaleAllowanceForCreditLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Securities, Available-for-Sale, Allowance for Credit Loss</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtSecuritiesAvailableForSaleAllowanceForCreditLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Debt Securities, Available-for-Sale, Allowance for Credit Loss, Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtSecuritiesAvailableForSaleAllowanceForCreditLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Debt Securities, Available-for-Sale, Allowance for Credit Loss, Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtSecuritiesAvailableForSaleAllowanceForCreditLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Debt Securities, Available-for-Sale, Allowance for Credit Loss, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtSecuritiesAvailableForSaleAllowanceForCreditLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Allowance for credit losses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfCollaborativeArrangementsAndNoncollaborativeArrangementTransactionsTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Collaborative Arrangement and Arrangement Other than Collaborative [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_CommonStockOptionsIssuedAndOutstandingMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock Options Issued and Outstanding [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_CommonStockOptionsIssuedAndOutstandingMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Common Stock Options Issued and Outstanding [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_CommonStockOptionsIssuedAndOutstandingMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common stock options issued and outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsRemainderOfFiscalYear_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Liability, to be Paid, Remainder of Fiscal Year</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsRemainderOfFiscalYear_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2026 (six months)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_LegalEntityAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Legal Entity [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Changes in operating assets and liabilities:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Adjustment to Reconcile Net Income to Cash Provided by (Used in) Operating Activity, Increase (Decrease) in Operating Capital [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Weighted Average Exercise Price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_OfferingCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other offering costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_OfferingCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Represent the amount offering costs.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_OfferingCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Offering Costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Tax Disclosure [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_ParticipationRightLiabilityTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Participation Right Liability [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_ParticipationRightLiabilityTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Participation Right Liability [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_ParticipationRightLiabilityTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Participation Right Liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdditionalPaidInCapitalMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Additional Paid-in Capital</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdditionalPaidInCapitalMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Additional Paid-in Capital [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInAccruedLiabilitiesAndOtherOperatingLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Accrued Liabilities and Other Operating Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInAccruedLiabilitiesAndOtherOperatingLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accrued research and development liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AmortizationOfRegulatoryAsset_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Amortization of Regulatory Asset</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AmortizationOfRegulatoryAsset_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Amortization of right-of-use assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueMeasurementFrequencyDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Measurement Frequency [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeStatementLocationAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statement of Income Location, Balance [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Summary of Significant Accounting Policies [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_TradingSymbol_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Trading Symbol</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Related Party Transaction [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_OutstandingCommonStockOptionsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Outstanding Common Stock Options [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_OutstandingCommonStockOptionsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Outstanding Common Stock Options [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_OutstandingCommonStockOptionsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Outstanding Common Stock Options [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ParticipationCostsPolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Participation Costs, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ParticipationCostsPolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Participation Right Liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash Provided by (Used in) Financing Activity, Including Discontinued Operation [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Financing activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Term</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Expected term, years</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueMeasurementsRecurringMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value, Recurring [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueMeasurementsRecurringMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Recurring Basis</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityExTransitionPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Ex Transition Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Liability, to be Paid</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total lease payments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Less: imputed interest</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Liability, Undiscounted Excess Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Less: imputed interest</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementEquityComponentsAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity Components [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NonoperatingIncomeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Nonoperating Income (Expense)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NonoperatingIncomeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total other income, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquityComponentDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity Component [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfShareBasedCompensationActivityTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement, Activity [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfShareBasedCompensationActivityTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Stock-based compensation components</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueByAssetClassAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Asset Class [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ClassOfStockDisclosuresAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Class of Stock Disclosures [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessAcquisitionAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IPOMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Initial Public Offering [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IPOMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">IPO [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IPOMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">IPO [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromPartnershipContribution_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds from Partnership Contribution</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromPartnershipContribution_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Contribution from BridgeBio Pharma</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromPartnershipContribution_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Fund Contribution</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_UniversityOfCaliforniaLicenseAgreementsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">University Of California License Agreements [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_UniversityOfCaliforniaLicenseAgreementsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">University Of California License Agreements [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_UniversityOfCaliforniaLicenseAgreementsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">UCSF License [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CollaborativeArrangementAccountingPolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Collaborative Arrangement, Accounting Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CollaborativeArrangementAccountingPolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Collaborative Arrangements</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_USTreasuryAndGovernmentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">US Treasury and Government [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_USTreasuryAndGovernmentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Treasury Bills</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementOfIncomeAndComprehensiveIncomeAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statement of Comprehensive Income [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsAndOtherReceivablesNetCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Receivables from related parties</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsAndOtherReceivablesNetCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounts and Other Receivables, Net, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_LiquidityPoliciesTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Liquidity Policies [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_LiquidityPoliciesTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Liquidity Policies</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_LiquidityPoliciesTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Liquidity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_MaximumMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Maximum [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_MaximumMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Maximum</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_MaximumMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Maximum [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentConvertibleConversionRatio1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Convertible, Conversion Ratio</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentConvertibleConversionRatio1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Ratio of Capital Stock Converted Into Common Stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfStockByClassTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Stock by Class [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfStockByClassTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Redeemable Convertible Preferred Stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_RangeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statistical Measurement [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Exercised</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangements by Share-Based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsWeightedAveragePeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share Based Compensation Arrangements By Share Based Payment Award Options Weighted Average Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsWeightedAveragePeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Share Based Compensation Arrangements By Share Based Payment Award Options Weighted Average Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock, Value, Issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockValue_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Fair value of common stock issuable to related party</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common stock, $0.0001 par value; 500,000,000 shares authorized as of June 30, 2026 and December 31, 2025, respectively; 80,088,931 and 79,991,768 shares issued and outstanding as of June 30, 2026 and December 31, 2025, respectively</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_DeferredUnderwritingFees_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Deferred underwriting fees</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_DeferredUnderwritingFees_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Represent the amount of deferred underwriting fees.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_DeferredUnderwritingFees_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Underwriting Fees</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash and Cash Equivalents [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash equivalents:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsForFees_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payments for Other Fees</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsForFees_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash fees</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_MinimumPercentageOfFairMarketValueOfBusinessAcquisitionToTrustAccountBalance_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Percentage of fair market value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_MinimumPercentageOfFairMarketValueOfBusinessAcquisitionToTrustAccountBalance_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Minimum percentage of fair market value of business acquisition to trust account balance.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_MinimumPercentageOfFairMarketValueOfBusinessAcquisitionToTrustAccountBalance_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Minimum Percentage Of Fair Market Value Of Business Acquisition To Trust Account Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ComprehensiveIncomeNetOfTaxAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ComprehensiveIncomeNetOfTaxAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Comprehensive loss, net of tax:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_ProbabilityWeightedExpectedReturnMethodTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Probability Weighted Expected Return Method Table Text Block</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_ProbabilityWeightedExpectedReturnMethodTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Probability Weighted Expected Return Method Table Text Block</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_ProbabilityWeightedExpectedReturnMethodTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Probability-Weighted Expected Return Method</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ImpairmentOrDisposalOfLongLivedAssetsPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Impairment of Long-Lived Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ImpairmentOrDisposalOfLongLivedAssetsPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Impairment or Disposal of Long-Lived Assets, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_CashBonusPaymentAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash Bonus Payment Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_CashBonusPaymentAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Cash Bonus Payment Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_CashBonusPaymentAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash bonus payment amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Expected volatility</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Volatility Rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockSharesAuthorized_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Preferred Stock, Shares Authorized</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockSharesAuthorized_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Shares authorized</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockSharesAuthorized_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Preferred stock, shares authorized</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TemporaryEquityAccretionToRedemptionValueAdjustment_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accretion of carrying value to redemption value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TemporaryEquityAccretionToRedemptionValueAdjustment_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Temporary Equity, Accretion to Redemption Value, Adjustment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RelatedPartyTransactionLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Related Party Transactions [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityRegistrantName_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Registrant Name</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_LeidosBiomedicalResearchIncMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Leidos Biomedical Research, Inc. [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_LeidosBiomedicalResearchIncMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Leidos Biomedical Research, Inc. [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Gross Unrealized Losses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Loss, before Tax</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Gross Unrealized Losses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherNonoperatingIncomeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other income (expense)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherNonoperatingIncomeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Nonoperating Income (Expense)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherNonoperatingIncomeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Other Nonoperating Income (Expense), Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdditionalPaidInCapital_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Additional paid-in capital</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdditionalPaidInCapital_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Additional Paid in Capital</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_InterestInMarketableSecurities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Interest in marketable securities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_InterestInMarketableSecurities_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Interest in marketable securities.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_InterestInMarketableSecurities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Interest In Marketable Securities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_PublicSharesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Public Shares [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_PublicSharesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Public Shares [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DepositAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Deposit account</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DepositAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deposit Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Tax provision</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Tax Expense (Benefit)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Income Tax Expense (Benefit), Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Provision for income tax</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_Black-ScholesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Black-Scholes [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_Black-ScholesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Black-Scholes [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueByMeasurementFrequencyAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Measurement Frequency [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromIssuanceOfCommonStock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds from Issuance of Common Stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromIssuanceOfCommonStock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Proceeds from Issuance of Common Stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_UpfrontFees_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Upfront Fees</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_UpfrontFees_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Upfront Fees</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_UpfrontFees_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Upfront Fees</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherGeneralExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other General Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherGeneralExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Material expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityCommonStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Common Stock, Shares Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConcentrationRiskCreditRisk_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Concentration Risk, Credit Risk, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConcentrationRiskCreditRisk_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Concentration of Credit Risk and Other Risks and Uncertainties</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CompensationRelatedCostsPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accrued Milestone Compensation Arrangements</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CompensationRelatedCostsPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Compensation Related Costs, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_ContraMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Contra [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_ContraMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Contra [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_ContraMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Contra [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accumulated Other Comprehensive Income (Loss), Net of Tax</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Accumulated Other Comprehensive Income (Loss), Net of Tax, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accumulated other comprehensive income (loss)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_TaxesPaidorPayableInterestToPayDissolutionExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Taxes payable to interest to pay dissolutions expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_TaxesPaidorPayableInterestToPayDissolutionExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Taxes paid or payable interest to pay dissolution expenses.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_TaxesPaidorPayableInterestToPayDissolutionExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Taxes Paidor Payable Interest To Pay Dissolution Expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RevenueFromCollaborativeArrangementExcludingRevenueFromContractWithCustomer_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Revenue from Collaborative Arrangement, Excluding Revenue from Contract with Customer</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RevenueFromCollaborativeArrangementExcludingRevenueFromContractWithCustomer_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Revenue from collaborative arrangement with related party</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Purchases of property and equipment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payments to Acquire Property, Plant, and Equipment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Payments to Acquire Property, Plant, and Equipment, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetAssetValuePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Net Asset Value Per Share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetAssetValuePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Net Asset Value Per Share, Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetAssetValuePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Net Asset Value Per Share, Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetAssetValuePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Net asset value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Number of Shares, Granted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfRestrictedCashAndCashEquivalentsTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Restrictions on Cash and Cash Equivalents [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfRestrictedCashAndCashEquivalentsTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Restrictions on Cash and Cash Equivalents</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TemporaryEquityByClassOfStockTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Temporary Equity, by Class of Stock [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Assets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Assets_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Total assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Assets_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Exercisable as of June 30, 2026</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeStatementAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Statement [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_TreasuryBillsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Treasury bills</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_TreasuryBillsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Treasury Bills [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_TreasuryBillsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Treasury Bills [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_ScheduleOfResearchAndDevelopmentExpenseTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Schedule of Research and Development Expense [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_ScheduleOfResearchAndDevelopmentExpenseTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Research and Development Expense [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_ScheduleOfResearchAndDevelopmentExpenseTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Research and Development Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationOptionAndIncentivePlansPolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationOptionAndIncentivePlansPolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stock-Based Compensation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LegalFees_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Legal Fees</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LegalFees_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Legal fees</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SaleOfStockNumberOfSharesIssuedInTransaction_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Number of units issued in transaction (in Shares)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SaleOfStockNumberOfSharesIssuedInTransaction_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Amount of public shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SaleOfStockNumberOfSharesIssuedInTransaction_lbl" xlink:role="http://www.xbrl.org/2009/role/netLabel">Exchanged shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SaleOfStockNumberOfSharesIssuedInTransaction_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Sale of Stock, Number of Shares Issued in Transaction</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesNewIssues_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Stock issued shares (in Shares)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesNewIssues_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Issued During Period, Shares, New Issues</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesNewIssues_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Shares issuable under the participation right</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Vested in Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Number of Shares, Vested and released</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Vesting of restricted stock, Share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareDiluted_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Diluted net income per ordinary share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareDiluted_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Earnings Per Share, Diluted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareDiluted_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Net loss per share attributable to common stockholders, diluted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueOptionQuantitativeDisclosuresLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value Measurements [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AuctionMarketPreferredSecuritiesStockSeriesTitleDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Auction Market Preferred Securities, Stock Series, Title [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfSegmentReportingInformationBySegmentTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Performance and Making Key Decisions Regarding Resource Allocation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfSegmentReportingInformationBySegmentTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Segment Reporting Information, by Segment [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_CityAreaCode_lbl" xlink:role="http://www.xbrl.org/2003/role/label">City Area Code</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_UnrealizedGainsOrLosses_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Unrealized Gains Or Losses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_UnrealizedGainsOrLosses_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Unrealized Gains Or Losses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_UnrealizedGainsOrLosses_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Unrealized gains or losses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_MaterialChangesAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Materail changes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_MaterialChangesAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Material Changes Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_MaterialChangesAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Material Changes Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OptionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Options Held [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OptionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Options Held [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_RepurchaseAgreementCounterpartyNameDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Counterparty Name [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_GeneralAndAdministrativeExpensesIncludeRelatedParty_lbl" xlink:role="http://www.xbrl.org/2003/role/label">General And Administrative Expenses Include Related Party</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_GeneralAndAdministrativeExpensesIncludeRelatedParty_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">General And Administrative Expenses Include Related Party</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseWeightedAverageRemainingLeaseTerm1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Lease, Weighted Average Remaining Lease Term</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseWeightedAverageRemainingLeaseTerm1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Weighted average remaining lease term</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LeaseExpirationDate1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lease Expiration Date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentNet_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, Plant and Equipment, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentNet_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Property, Plant and Equipment, Net, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentNet_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Property and equipment, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingIncomeLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Loss from operations</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingIncomeLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Income (Loss)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PurchaseTransactionPolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Material Related Party Transactions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PurchaseTransactionPolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Transaction between Entities under Common Control [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RetainedEarningsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accumulated Deficit</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RetainedEarningsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Retained Earnings [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash and Cash Equivalents [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensation_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Share-based compensation expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensation_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement, Noncash Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensation_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Share-Based Payment Arrangement, Noncash Expense, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensation_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stock-based compensation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsOfStockIssuanceCosts_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Public Shares issuance costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsOfStockIssuanceCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payments of Stock Issuance Costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_TSAAmendmentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">TSA</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_TSAAmendmentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">TSA Amendment [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_TSAAmendmentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">TSA Amendment [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_CollaborationAgreementsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Collaboration Agreements [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_CollaborationAgreementsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Collaboration Agreements [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseWeightedAverageDiscountRatePercent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Lease, Weighted Average Discount Rate, Percent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseWeightedAverageDiscountRatePercent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Weighted average remaining lease term discount rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiabilityNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Lease, Liability, Noncurrent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiabilityNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Operating lease liability, noncurrent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueInputsLevel1Member_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value, Inputs, Level 1 [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueInputsLevel1Member_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Level 1</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ClassOfStockLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Class of Stock [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInFinancingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash Provided by (Used in) Financing Activity, Including Discontinued Operation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInFinancingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net cash provided by financing activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfConversionsOfStockTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Conversions of Stock [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfConversionsOfStockTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Shares Reserved for Issuance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NonoperatingIncomeExpenseAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Nonoperating Income (Expense) [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NonoperatingIncomeExpenseAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other income, net:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_MilestonePayment_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Milestone Payment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_MilestonePayment_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Milestone payment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_MilestonePayment_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Milestone payment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Antidilutive Securities Excluded from Computation of Diluted Net Loss Per Share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CorporateDebtSecuritiesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Corporate Debt Securities [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CorporateDebtSecuritiesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Corporate Debt Securities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_LawrenceLivermoreNationalSecurityLicenseAndCooperativeResearchAndDevelopmentAgreementsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lawrence Livermore National Security License And Cooperative Research And Development Agreements [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_LawrenceLivermoreNationalSecurityLicenseAndCooperativeResearchAndDevelopmentAgreementsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Lawrence Livermore National Security License And Cooperative Research And Development Agreements [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_LawrenceLivermoreNationalSecurityLicenseAndCooperativeResearchAndDevelopmentAgreementsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">LLNS CRADA [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityInteractiveDataCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Interactive Data Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeStatementLocationDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statement of Income Location, Balance [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash Provided by (Used in) Operating Activity, Including Discontinued Operation [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Operating activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccretionAmortizationOfDiscountsAndPremiumsInvestments_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accretion (Amortization) of Discounts and Premiums, Investments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccretionAmortizationOfDiscountsAndPremiumsInvestments_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel">Net accretion of premiums and discounts on marketable securities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_DiscountRate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Discount rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_DiscountRate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Discount Rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_DiscountRate_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Discount Rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashEquivalentsAtCarryingValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash Equivalents, at Carrying Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashEquivalentsAtCarryingValue_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Cash Equivalents, at Carrying Value, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashEquivalentsAtCarryingValue_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Cash equivalents</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OptionIndexedToIssuersEquityTypeDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Option Indexed to Issuer's Equity, Type [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_InvestmentCategoryAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Investment Category [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_InvestmentCategoryAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Investment Category [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityTaxIdentificationNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Tax Identification Number</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share Price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfCommonStockOutstandingRollForwardTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Common Stock Outstanding Roll Forward [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfCommonStockOutstandingRollForwardTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">The Company's Outstanding Common Stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_ThresholdNumberofBusinessDaystoRedeemPublicSharesFromCombinationPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Promptly business days</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_ThresholdNumberofBusinessDaystoRedeemPublicSharesFromCombinationPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Represents the threshold number of business days to redeem Public Shares from Combination Period if the Company has not completed an Initial Business Combination.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_ThresholdNumberofBusinessDaystoRedeemPublicSharesFromCombinationPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Threshold Numberof Business Daysto Redeem Public Shares From Combination Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_TrustAccountMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Trust Account [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_TrustAccountMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Trust Account [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MarketableSecuritiesUnrealizedGainLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Marketable Security, Unrealized Gain (Loss)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MarketableSecuritiesUnrealizedGainLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Unrealized losses on marketable securities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MarketableSecuritiesUnrealizedGainLoss_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Unrealized gains (losses) on marketable securities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MarketableSecuritiesUnrealizedGainLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Unrealized gain (loss) on marketable securities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_IncomeFromTransitionServicesAgreements_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income From Transition Services Agreements</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_IncomeFromTransitionServicesAgreements_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Income from transition services agreements</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_IncomeFromTransitionServicesAgreements_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Income From Transition Services Agreements</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_LocalPhoneNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Local Phone Number</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RelatedPartyTransactionDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Related Party Transaction [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedStockOptions_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Unrecognized stock based expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedStockOptions_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement, Nonvested Award, Option, Cost Not yet Recognized, Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShortTermLeaseCost_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Short-Term Lease, Cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShortTermLeaseCost_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Short-term lease costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfServicingAssetsAtAmortizedValueTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Servicing Asset at Amortized Cost [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfServicingAssetsAtAmortizedValueTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Amortized Cost and Fair Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RevenueRemainingPerformanceObligationPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Shares Purchase Percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RevenueRemainingPerformanceObligationPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Revenue, Remaining Performance Obligation, Percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_SharesReservedForIssuanceUnderTheEmployeeStockPurchasePlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Shares Reserved For Issuance Under The Employee Stock Purchase Plan [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_SharesReservedForIssuanceUnderTheEmployeeStockPurchasePlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Shares Reserved For Issuance Under The Employee Stock Purchase Plan [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_SharesReservedForIssuanceUnderTheEmployeeStockPurchasePlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Shares reserved for issuance under the employee stock purchase plan</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountingPoliciesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Summary of Significant Accounting Policies [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_ScenarioPreviouslyReportedMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Previously Reported [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFour_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Liability, to be Paid, Year Four</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFour_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2030</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_CommittedCashBonusAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Committed cash bonus amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_CommittedCashBonusAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Committed Cash Bonus Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_CommittedCashBonusAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Committed Cash Bonus Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ClassOfStockDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Class of Stock [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommercialPaperMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Commercial Paper [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommercialPaperMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Commercial Paper</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Weighted average period, unvested common stock options</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccruedProfessionalFeesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accrued Professional Fees, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccruedProfessionalFeesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accrued professional services</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashCashEquivalentsAndShortTermInvestments_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">cash, cash equivalents, and marketable securities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashCashEquivalentsAndShortTermInvestments_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash, Cash Equivalents, and Short-Term Investments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashCashEquivalentsAndShortTermInvestments_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Cash, Cash Equivalents, and Short-Term Investments, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_IssuanceOfSeriesBRedeemableConvertiblePreferredStockForCashConsiderationAndSettlementOfParticipationRightLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Issuance Of Series B Redeemable Convertible Preferred Stock For Cash Consideration And Settlement Of Participation Right Liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_IssuanceOfSeriesBRedeemableConvertiblePreferredStockForCashConsiderationAndSettlementOfParticipationRightLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Issuance Of Series B Redeemable Convertible Preferred Stock For Cash Consideration And Settlement Of Participation Right Liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="bbot_IssuanceOfSeriesBRedeemableConvertiblePreferredStockForCashConsiderationAndSettlementOfParticipationRightLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Issuance of Series B redeemable convertible preferred stock for cash consideration and settlement of participation right liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfStockByClassTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock, Class of Stock [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityEmergingGrowthCompany_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Emerging Growth Company</link:label>
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  <xsd:element id="bbot_EmployeeStockPurchasePlanMember" name="EmployeeStockPurchasePlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="bbot_OutstandingCommonStockOptionsMember" name="OutstandingCommonStockOptionsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="bbot_HelixCommonStockSubjectToRedemptionPriorToTheClosing" name="HelixCommonStockSubjectToRedemptionPriorToTheClosing" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="bbot_LawrenceLivermoreNationalSecurityLLCMember" name="LawrenceLivermoreNationalSecurityLLCMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="bbot_TransactionCosts" name="TransactionCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="bbot_SharesIssuableUnderTheParticipationRightMember" name="SharesIssuableUnderTheParticipationRightMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="bbot_MilestoneLiability" name="MilestoneLiability" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="bbot_CollaborationAgreementsAbstract" name="CollaborationAgreementsAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="bbot_ShareBasedCompensationArrangementByShareBasedPaymentAwardPerformanceBaseAwardsExpense" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardPerformanceBaseAwardsExpense" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="bbot_ParticipationRightLiabilityPolicyTextBlock" name="ParticipationRightLiabilityPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="bbot_PublicSharesPercentage" name="PublicSharesPercentage" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="bbot_Short-TermMarketableSecuritiesMember" name="Short-TermMarketableSecuritiesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="bbot_ProbabilityWeightedExpectedReturnMethodSeriesB" name="ProbabilityWeightedExpectedReturnMethodSeriesB" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="bbot_OfferingCosts" name="OfferingCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="bbot_CommonStockOptionsIssuedAndOutstandingMember" name="CommonStockOptionsIssuedAndOutstandingMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="bbot_PercentageofRedemptioninConnectionWithInitialPublicShares" name="PercentageofRedemptioninConnectionWithInitialPublicShares" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="bbot_SharesReservedForIssuanceUnderStockOptionAndIncentivePlanMember" name="SharesReservedForIssuanceUnderStockOptionAndIncentivePlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="bbot_GeneralAndAdministrativeExpensesIncludeRelatedParty" name="GeneralAndAdministrativeExpensesIncludeRelatedParty" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="bbot_CashBonusPaymentAmount" name="CashBonusPaymentAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="bbot_TrustAccountPublicPricePerShare" name="TrustAccountPublicPricePerShare" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="bbot_UnrealizedGainsOrLosses" name="UnrealizedGainsOrLosses" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="bbot_ResearchAndDevelopmentExpensesIncludeRelatedParty" name="ResearchAndDevelopmentExpensesIncludeRelatedParty" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="bbot_ParticipationRightLiability" name="ParticipationRightLiability" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="bbot_UnderwritingDiscounts" name="UnderwritingDiscounts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="bbot_InterestInMarketableSecurities" name="InterestInMarketableSecurities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="bbot_ShareBasedCompensationArrangementByPerformanceBasedMilestoneAwards" name="ShareBasedCompensationArrangementByPerformanceBasedMilestoneAwards" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="bbot_ShareBasedCompensationExpenseCarveOutMethodology" name="ShareBasedCompensationExpenseCarveOutMethodology" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="bbot_ResearchAndDevelopmentTrialsAndConsumablesExpenseMember" name="ResearchAndDevelopmentTrialsAndConsumablesExpenseMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="bbot_PublicSharesMember" name="PublicSharesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="bbot_InducementPlanMember" name="InducementPlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="bbot_TreasuryBillsMember" name="TreasuryBillsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="bbot_TotalCommonStockIssuedAndOutstanding" name="TotalCommonStockIssuedAndOutstanding" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="bbot_AccruedInterestOnMarketableSecurities" name="AccruedInterestOnMarketableSecurities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="bbot_LiquidityPoliciesTextBlock" name="LiquidityPoliciesTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="bbot_Long-TermMarketableSecuritiesMember" name="Long-TermMarketableSecuritiesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="bbot_ResearchAndCollaborationAgreementMember" name="ResearchAndCollaborationAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="bbot_ScheduleOfResearchAndDevelopmentExpenseTableTextBlock" name="ScheduleOfResearchAndDevelopmentExpenseTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="bbot_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsWeightedAveragePeriod" name="ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsWeightedAveragePeriod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="bbot_SummaryofSignificantAccountingPoliciesDetailsTable" name="SummaryofSignificantAccountingPoliciesDetailsTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="bbot_RedemptionOfHelixCommonStock" name="RedemptionOfHelixCommonStock" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="bbot_FairValueMeasurementsTable" name="FairValueMeasurementsTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="bbot_PayablesToRelatedParties" name="PayablesToRelatedParties" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="bbot_CommonStockOfHelixIssuedInThePIPEFinancing" name="CommonStockOfHelixIssuedInThePIPEFinancing" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="bbot_DebtSecuritiesAvailableForSaleEstimatedFairValue" name="DebtSecuritiesAvailableForSaleEstimatedFairValue" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="bbot_BusinessCombinationMember" name="BusinessCombinationMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="bbot_WorkingCapitalDeficit" name="WorkingCapitalDeficit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="bbot_InterestToPayDissolutionExpenses" name="InterestToPayDissolutionExpenses" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="bbot_LegacyBBOTCommonStock" name="LegacyBBOTCommonStock" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="bbot_MilestonePaymentsUnderInLicensingAgreementsPolicyTextBlock" name="MilestonePaymentsUnderInLicensingAgreementsPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="bbot_StockOptionAndIncentivePlanMember" name="StockOptionAndIncentivePlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="bbot_RelatedPartyIncomeAndExpensesMember" name="RelatedPartyIncomeAndExpensesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="bbot_DiscountRate" name="DiscountRate" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="bbot_AllocatedOperatingExpensesMember" name="AllocatedOperatingExpensesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="bbot_PIPEFinancingAndDe-SPACTransactionTextBlock" name="PIPEFinancingAndDe-SPACTransactionTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="bbot_UnpaidPropertyAndEquipmentIncludedInOtherAccruedLiabilities" name="UnpaidPropertyAndEquipmentIncludedInOtherAccruedLiabilities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="bbot_ScheduleOfSharesReservedForIssuanceTableTextBlock" name="ScheduleOfSharesReservedForIssuanceTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="bbot_LicenseAndCollaborationAgreementsAbstract" name="LicenseAndCollaborationAgreementsAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="bbot_DescriptionofOrganizationandBusinessOperationsDetailsTable" name="DescriptionofOrganizationandBusinessOperationsDetailsTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="bbot_UpfrontFees" name="UpfrontFees" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="bbot_CommonStockOptionsMember" name="CommonStockOptionsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="bbot_DeferredUnderwritingFees" name="DeferredUnderwritingFees" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="bbot_OfferingPriceRelatedToSeriesB" name="OfferingPriceRelatedToSeriesB" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="bbot_FacilitiesAndOtherExpensesMember" name="FacilitiesAndOtherExpensesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="bbot_ParticipationRightLiabilityTableTextBlock" name="ParticipationRightLiabilityTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="bbot_SharesReservedForIssuance" name="SharesReservedForIssuance" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="bbot_ProbabilityWeightedExpectedReturnMethodTableTextBlock" name="ProbabilityWeightedExpectedReturnMethodTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="bbot_MinimumPercentageOfFairMarketValueOfBusinessAcquisitionToTrustAccountBalance" name="MinimumPercentageOfFairMarketValueOfBusinessAcquisitionToTrustAccountBalance" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="bbot_LegacyBBOTCommonStockOption" name="LegacyBBOTCommonStockOption" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="bbot_MinimumMaturityofInvestment" name="MinimumMaturityofInvestment" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="bbot_NetProceedsFromSaleOfUnits" name="NetProceedsFromSaleOfUnits" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="bbot_DilutedOutstandingCapitalization" name="DilutedOutstandingCapitalization" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="bbot_Black-ScholesMember" name="Black-ScholesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="bbot_TaxesPaidorPayableInterestToPayDissolutionExpenses" name="TaxesPaidorPayableInterestToPayDissolutionExpenses" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="bbot_ShareBasedCompensationArrangementByEquityAwardsIssuedByBridgeBioPharma" name="ShareBasedCompensationArrangementByEquityAwardsIssuedByBridgeBioPharma" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="bbot_ContraMember" name="ContraMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="bbot_ScheduleOfResearchAndDevelopmentExpensesTableTextBlock" name="ScheduleOfResearchAndDevelopmentExpensesTableTextBlock" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="bbot_QualifyingLiquidityEventProbability" name="QualifyingLiquidityEventProbability" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="bbot_DeferredDe-SPACTransactionCostsIncludedInAccruedProfessionalServicesAndOtherAccruedLiabilities" name="DeferredDe-SPACTransactionCostsIncludedInAccruedProfessionalServicesAndOtherAccruedLiabilities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="bbot_TransitionServicesAgreementMember" name="TransitionServicesAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="bbot_WorkingCapitalLoan" name="WorkingCapitalLoan" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="bbot_TrustAccountMember" name="TrustAccountMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="bbot_LeidosBiomedicalResearchIncMember" name="LeidosBiomedicalResearchIncMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="bbot_RCALicenseGrantMember" name="RCALicenseGrantMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="bbot_UniversityOfCaliforniaLicenseAgreementsMember" name="UniversityOfCaliforniaLicenseAgreementsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="bbot_LeidosBiomedicalResearchLicenseAndCooperativeResearchAndDevelopmentAgreementsMember" name="LeidosBiomedicalResearchLicenseAndCooperativeResearchAndDevelopmentAgreementsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="bbot_MaterialChangesAmount" name="MaterialChangesAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="bbot_LawrenceLivermoreNationalSecurityLicenseAndCooperativeResearchAndDevelopmentAgreementsMember" name="LawrenceLivermoreNationalSecurityLicenseAndCooperativeResearchAndDevelopmentAgreementsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="bbot_SharesReservedForIssuanceUnderTheInducementPlanMember" name="SharesReservedForIssuanceUnderTheInducementPlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="bbot_OtherNonCashAdjustmentsNet" name="OtherNonCashAdjustmentsNet" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="bbot_BridgeBioPharmaMember" name="BridgeBioPharmaMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="bbot_ShareBasedCompensationArrangementByCommonStockOptionsIssuedByTheCompany" name="ShareBasedCompensationArrangementByCommonStockOptionsIssuedByTheCompany" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="bbot_InvestmentCategoryDomain" name="InvestmentCategoryDomain" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="bbot_SharesReservedForIssuanceUnderTheEmployeeStockPurchasePlanMember" name="SharesReservedForIssuanceUnderTheEmployeeStockPurchasePlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="bbot_TwoThousandSixteenPlanMember" name="TwoThousandSixteenPlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="bbot_SharesPurchasePercentage" name="SharesPurchasePercentage" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="bbot_ScheduleOfClassAOrdinarySharesSubjectToRedemptionReflectedAbstract" name="ScheduleOfClassAOrdinarySharesSubjectToRedemptionReflectedAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="bbot_InvestmentCategoryAxis" name="InvestmentCategoryAxis" type="xbrli:stringItemType" substitutionGroup="xbrldt:dimensionItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="bbot_EmergingGrowthCompanyPolicyTextBlock" name="EmergingGrowthCompanyPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="bbot_IntrinsicValue" name="IntrinsicValue" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="bbot_NoPerformanceMilestoneAwards" name="NoPerformanceMilestoneAwards" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="bbot_ConsiderationRatio" name="ConsiderationRatio" type="xbrli:pureItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="bbot_SeriesSeedMember" name="SeriesSeedMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="bbot_RemainsDilutedOutstandingCapitalization" name="RemainsDilutedOutstandingCapitalization" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="bbot_InitialPublicOfferingPricePerShare" name="InitialPublicOfferingPricePerShare" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="bbot_IssuanceOfSeriesBRedeemableConvertiblePreferredStockForCashConsiderationAndSettlementOfParticipationRightLiability" name="IssuanceOfSeriesBRedeemableConvertiblePreferredStockForCashConsiderationAndSettlementOfParticipationRightLiability" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="bbot_TSAAmendmentMember" name="TSAAmendmentMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="bbot_CashUnderwritingFee" name="CashUnderwritingFee" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="bbot_CommittedCashBonusAmount" name="CommittedCashBonusAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
</xsd:schema>
