I found if transferring to Thailand via Remitly or similar transfer companies the limit is 50k BT. But if you are transferring from a high street bank you can transfer 800k TB no problem.
From one Thai bank to another Thai bank the limit is set on the app. You can set from 50k TB to 1.5 million TB.
. my partner is Thai and I am named on a yellow book. This gives me permanent address. I got refused several times straight off.But just keep trying and then one bank make a few phone calls and said yes. Bit of luck I guess.