Query Locks Table And Takes Long Time to Run

I have a query that can take a long time to run. I tried running the same query in a test server and it runs very quick. However, in production it seems to hang and causes blocking of other queries. Where do I begin to find a solution for this? Below is my code and the plan... https://www.brentozar.com/pastetheplan/?id=ryAQWfL2X The issue seems to be with the CTE statement. Is there a more efficient way of writing this? -- table to store break details CREATE TABLE #PositionReconciliationCurrentBreaks ( TransactionKey INT, BreakOriginationDate DATE, BreakAge DECIMAL (18,0) ); TRUNCATE TABLE #PositionReconciliationCurrentBreaks; WITH PreviousRecBreaks_CTE -- get breaks from previous rec AS ( SELECT MAX(i.InvestmentID) AS InvestmentID, PRT.PositionDate, PRT.PositionReconciliationDetailKey, MAX(PRT.PositionReconciliationTransactionKey) AS PositionReconciliationTransactionKey, PRT.InvestmentKey, MAX(PRT.GenevaInvestmentKey) AS GenevaInvestmentKey, MAX(PRT.BrokerInvestmentKey) AS BrokerInvestmentKey, PRT.PaymentCurrencyKey, PRT.AccountKey, CASE WHEN MAX(PRT.BreakOriginationDate) = '2100-01-01' THEN NULL ELSE MAX(PRT.BreakOriginationDate) END AS BreakOriginationDate, MAX(PRT.BreakAge) AS BreakAge, SUM(ISNULL(PRT.GenevaQuantity,0)) AS GenevaQuantity, SUM(ISNULL(PRT.BrokerQuantity,0)) AS BrokerQuantity FROM [Fund.Accounting.Model.PositionReconciliation].PositionReconciliationTransaction PRT -- get transactions from previous rec INNER JOIN [Fund.Accounting.Model.PositionReconciliation].PositionReconciliationDetail TRD -- check details to get Action on transaction ON TRD.PositionReconciliationDetailKey = PRT.PositionReconciliationDetailKey -- join on Detail Key inner join [Fund.Accounting.Model.TradeReconciliation].Investment i -- add in investmentID for debugging purpose ON i.InvestmentKey = PRT.InvestmentKey INNER JOIN [Fund.Accounting.Model].[ReconciliationActions] RA -- actions ON RA.ReconciliationActionID=TRD.ReconciliationActionID AND (TRD.PositionCommentKey IS NOT NULL) --approved breaks must have a comment. AND RA.Name 'Suppress' -- ensure not suppressed AND RA.Name 'Auto Match' -- ensure not perfect match - we do want to include cross references with a qty diff WHERE PRT.PositionReconciliationID = @PreviousPositionReconciliationId -- previous rec GROUP BY -- added grouping for quantity breaks as x-refs will be 2 separate lines in PositionReconciliationTransaction tbl; We group to force this as 1 line PRT.PositionDate, PRT.PositionReconciliationDetailKey, PRT.InvestmentKey, PRT.PaymentCurrencyKey, PRT.AccountKey ),CurrentRecBreaks_CTE -- get breaks from current rec AS ( SELECT MAX(i.InvestmentID) AS InvestmentID, PRT.PositionDate, PRT.PositionReconciliationDetailKey, MAX(PRT.PositionReconciliationTransactionKey) AS PositionReconciliationTransactionKey, PRT.InvestmentKey, MAX(PRT.GenevaInvestmentKey) AS GenevaInvestmentKey, MAX(PRT.BrokerInvestmentKey) AS BrokerInvestmentKey, PRT.PaymentCurrencyKey, PRT.AccountKey, CASE WHEN MAX(PRT.BreakOriginationDate) = '2100-01-01' THEN NULL ELSE MAX(PRT.BreakOriginationDate) END AS BreakOriginationDate, MAX(PRT.BreakAge) AS BreakAge, SUM(ISNULL(PRT.GenevaQuantity,0)) AS GenevaQuantity, SUM(ISNULL(PRT.BrokerQuantity,0)) AS BrokerQuantity FROM [Fund.Accounting.Model.PositionReconciliation].PositionReconciliationTransaction PRT -- get transactions from previous rec INNER JOIN [Fund.Accounting.Model.PositionReconciliation].PositionReconciliationDetail TRD -- check details to get Action on transaction ON TRD.PositionReconciliationDetailKey = PRT.PositionReconciliationDetailKey -- join on Detail Key inner join [Fund.Accounting.Model.TradeReconciliation].Investment i -- add in investmentID for debugging purpose ON i.InvestmentKey = PRT.InvestmentKey LEFT JOIN [Fund.Accounting.Model].[ReconciliationActions] RA -- actions ON RA.ReconciliationActionID=TRD.ReconciliationActionID AND RA.Name 'Suppress' -- ensure not suppressed AND RA.Name 'Auto Match' -- ensure not perfect match - we do want to include cross references with a qty diff WHERE PRT.PositionReconciliationID = @PositionReconciliationID -- current rec GROUP BY -- added grouping for quantity breaks as x-refs will be 2 separate lines in PositionReconciliationTransaction tbl; We group to force this as 1 line PRT.PositionDate, PRT.PositionReconciliationDetailKey, PRT.InvestmentKey, PRT.PaymentCurrencyKey, PRT.AccountKey ) INSERT INTO #PositionReconciliationCurrentBreaks ( TransactionKey, BreakOriginationDate, BreakAge ) SELECT -- get breaks in current rec that also appeared in previous rec C.PositionReconciliationTransactionKey ,ISNULL(P.BreakOriginationDate,@PreviousPositionReconciliationPeriod) --set ro previous date if it is first time presence. ,CASE DATEDIFF(DAY, P.PositionDate, C.PositionDate) WHEN 0 THEN 1 --set to 1 day old, if it is 1st time ELSE ISNULL(P.BreakAge,0) + DATEDIFF(DAY, P.PositionDate, C.PositionDate) -- get no. of days difference between current rec and previous one END AS BreakAge FROM PreviousRecBreaks_CTE P INNER JOIN CurrentRecBreaks_CTE C ON P.AccountKey = C.AccountKey AND P.PaymentCurrencyKey=C.PaymentCurrencyKey AND P.InvestmentKey=C.InvestmentKey --AND (P.GenevaInvestmentKey=C.GenevaInvestmentKey -- OR P.BrokerInvestmentKey=C.BrokerInvestmentKey) AND P.GenevaQuantity=C.GenevaQuantity AND P.BrokerQuantity=C.BrokerQuantity WHERE NOT EXISTS( -- exclude breaks that are now perfect matches (or suppressed???) SELECT D.PositionReconciliationDetailKey FROM [Fund.Accounting.Model.PositionReconciliation].PositionReconciliationDetail D INNER JOIN -- join on AggregatePositionReconciliationTransaction so we can get the Qty Diff value [Fund.Accounting.Facade.PositionReconciliation].[AggregatePositionReconciliationTransaction] (@PositionReconciliationID,NULL,NULL) A ON A.PositionReconciliationDetailKey = D.PositionReconciliationDetailKey WHERE D.PositionReconciliationID = @PositionReconciliationID -- current rec AND A.QuantityDifference = 0 -- perfect matches AND D.PositionReconciliationDetailKey = C.PositionReconciliationDetailKey -- join details to transactions );