I don’t understand what you might be referring to, @ShaneAU. Before v17.11.20, all cash transactions, whether receipt or payment, had no option to be designated as tax-exclusive or tax-inclusive. All, without exception, were tax-inclusive. This was true long ago, before Bank Accounts and Cash Accounts tabs were combined into the single Cash Accounts tab. It was true during the period when all cash and bank accounts were handled under the Cash Accounts tab. And it was still true when the tabs were split apart again at v17.9.0. Prior to v17.11.20, the only way to show a tax-exclusive sale or purchase was to enter an invoice. And then, the default was tax-exclusive.
When creating those receipts and payments prior to v17.11.20, there was no Subtotal line. There was a Total line and another listing how much tax was included. So I don’t see how your November 17, 2017 bank transaction could have the components you listed, assuming it was really created on that date.
When the change was introduced at v17.11.20, prior receipts and payments, which could only have been created as tax-inclusive, automatically had the
[_] Amounts are tax inclusive box checked. I have confirmed that all my past cash transactions, no matter which version of the program they were created under and whether in a cash or bank account, has the box checked. That is so whether a tax code was applied or not. My interpretation of this conversion action was that it was specifically done to preclude the type of problem you describe.
Since you say you have a $300 bank transaction from before the change, you must have saved a paper copy or PDF. Or perhaps you are maintaining older, operating versions of Manager. Can you provide screen shots supporting you description of what you see, such as a copy of the completed form and verification of the version number of the program?