@Ot**
there hasn't been a pandemic with borders closed before in the many years you have lived here, this is unprecedented.
I'm not trying to be difficult or to do a "if you don't like it, go home", I'm more just trying to get across from a purely practical point of view _if you (or Paul) have 800k_ you may be best putting that in a Thai bank account ASAP and doing a regular extension.
Maybe before you were able to do border runs and this is what you like to do but that isn't likely to be possible any time soon.
So your options are _likely_ going to be to go home before 31 July, or extend. If you have the option of extending, you are in a better position than many people, and it might be in your best interest.
There is IMO no issue with having 800k in a Thai bank. There's no problem moving it back out either, despite what people might tell you. If you do it with the same bank it came in to there isn't even any paperwork, they automatically log that you brought it in and can send it back out, it's automatic.