Your OA visa expiry is Nov. 2024 I assume. If you exit and re-enter Thailand before visa expiry Nov. 24 you will get another 12 months entry providing your current health insurance is valid for 12 months at the time you re-enter Thailand otherwise you will be stamped in to the expiry of your health insurance. Yes on arrival with an OA they will ask to see your health insurance.
To kill off the OA leave prior Nov. 24 and return AFTER the OA visa expiry date with a tourist visa or exempt and the extensions you can get from them, or return with a 90 day Non O e-visa from home country and continue 1 year extensions on the Non O, no health insurance required, will need a Thai bank account. You may need health insurance to apply for the Non O e-visa in home country not sure now what they are doing with that, I used my existing valid insurance from my killed off OA and got the Non O for my return a couple years ago.