not sure which immigration offices that applies to... I was told that they do not care where the initial ฿800k comes from. I'm not clear if there's a difference between getting non-o abroad where the ฿800k must be seasoned and doesn't matter where it comes from, or getting the non-o in country where the ฿800k is required to apply.
Usually bank wire is cheaper for larger amounts. Bank fees for sending wire transactions vary. Check with your bank and do the arithmetic to see if wire or Wise is cheaper for the amount you are transferring. For me, break even is about ฿150k but your mileage will vary.
There's a good chance you will have to apply for a new non-o. If you're next extension isn't until mar-2026, how did you get your extension that would start Mar-2025?
I believe most want it current within the last 5 business days. Your passbook showing current balance should be obtained on the day of your extension application.
Keep/put as little capital in Thailand as possible. Invest your capital in your home country and transfer what you need (visa requirements, expenses) from the earnings. Rent, don't buy. Real estate is not an investment for foreigners in Thailand.