Click on “Sales Invoices”.
Click on “[There is at least one invoice with pending late payment fee]”.
The result is a list of invoices to which automatic late payment fees are waiting to be applied. To the right of each line, there is a checked check mark. Why not allow the user to selectively uncheck these?
Of course the developer would need to decide whether the unchecked item should reappear the next time the user arrives on this screen, or whether unchecking would turn off automatic late fee generation for the particular invoice. Either way, it would allow the user to selectively waive (or postpone) late payment fees for individual invoices.