Discount invoice from "next invoice number" computation

Sorry to bump this topic, but I’m really struggling to even find a workaround to this. Whenever I put in the Amazon invoices, there’s just no way for me to get my recurring invoices back on track. I’d love any suggestions as to how I can ameliorate the situation (without disabling auto-invoicing from Amazon, and without having to manually approve every recurring invoice, and fixing the numbers before sending them out)

In reference to the following post: Set next invoice number - #30 by Glenn I think there is another potential option.

The referenced thread deals with two potential solutions:

(1) Having a company-wide setting that indicate the next invoice number to be used.
(2) Having a setting that dictates the next invoice numbering policy, either:
(a) Last created +1 (the current system)
(b) Lexicographically highest +1

There was vague support for (1), but as an alternative to my proposal (in my previous post), I would like to propose a variation on (1), and having an optional setting that allows you to specify the next invoice number.

The discussion in #5444 centres around a field that would need to be updated every time an invoice is created, with the next number to be used, however, I propose the field to be optional.

When creating an invoice, if this field is unset, the system would default to “last created +1”, as usual. If this field is set, then it would use the number from this field for the next invoice number, and if the resulting invoice is saved, then this field is unset - effectively reverting to the original logic.

I’d really like a solution to this - or even a workaround to get my invoicing back on track.

Best wishes,
Tom