What are the implications of the under consideration period for my Non-O visa and re-entry permit in Thailand?

I'd like to clarify about the under consideration period please.

I have a Non-O (Thai wife) visa, and am on an annual extension with a multi-reentry permit (current extension and re-entry both issued at CW). Expiring 24/11/25. I'm in Bangkok, so will be applying at Chengwatthana.

If I've understood correctly, I can apply for the next year when I've got 45 days or less remaining (i.e. from 10/10/25 onwards), and will get 21 days under consideration from the application date.

If I apply on 10/10/25, I'd go back on 31/10/25, which is before my current annual extension expires.

On 31/10/25 would I get stamped for the next 1 year until 24/11/26, and be able to apply for a multi-reentry until 24/11/26? Or do I need to come back at a later date to get the extension stamped in?

If I'm planning to travel overseas during the under consideration period, would the existing re-entry permit still be valid, or does it get cancelled by the next year application, needing a new re-entry permit to cover the under consideration period?