Take a look at:

1. Reconcilation Models

Accounting --> Configuration --> Accounting --> Reconcilation Models

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This example gives you a button on the Bank Statement reconcilation screen to record the sweep amount.  If you can reliably tell from the bank statement line which text is used each time, you can use the "auto validate" option of "Suggest counterpart values. " and tell Odoo what text string the bank statement line contains (or use a regex expression).

2. Automated Transfers

Accounting --> Accounting --> Management --> Automatic Transfers

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