„and for some reason the IO gave me a visa expiration date of 29 November 2025”
No. He didn’t give you a “new visa expiration date”
He gave you a STAY PERMIT which is valid until November 29, 2025
Your “visa expiration date” is still December this year.
After the expiry of your visa validity, you have no re-entry permit any more.
So if you were to exit Thailand in February for a few weeks, you would need to buy a single re-entry permit in order to keep your stay permit until 29 November 2025 alive.
You do not have to do the “1-year extension of stay permit” by next week, yet.
You can wait until 29 October 2025, before you apply for the “1-Year Extended Stay Permit”
my guess, you weren't just warned, you also got "flagged" in the Immigrations central computer. So any Immigration official would be able to see that you have been warned previously. I would heed James Miller's advice
you can only register online by yourself, if your landlord gives you the login-ID and the password. By this you wouldn't waste his time. Maybe he will agree
pointed out. And seeing that you haven't gotten a 60-days family visit extension, yet, on top of your last entry, and you are aiming at the 12-months Extension of stay based on marriage to a Thai wife, yes, it should be accepted
yes, you are right, you can only use the 60-days family visit once per entry. So maybe you will be allowed to get another one on Immigration if it is really "per entry" and not per "calendar year". As it would be the only one upon your current 60-days stay permit out of a visa-exempt entry. Visit Immigration and ask. You would not need to exit, and meet the deposit seasoning requirement during these extra 60 days
as being married to a Thai wife, you could apply on Immigration for the 60-days "family visit" extension before your current stay permit expires. Then you don't need to do the border bounce
as being married to a Thai wife, you could apply on Immigration for the 60-days "family visit" extension. Then do the border bounce and another 60-days visa exempt entry after that