@Nigel ******
you are correct sir. Only way to use 65K monthly income from the start is by using an income affidavit that is verified by your countries embassy in Thailand. If they don't do that, it's simply not possible. Have to start with the 800K and then switch later if needed, by maintaining the requirements for the 800K method throughout the year, while simultaneously transferring 65K in every month.
My father uses the affidavit every year. They usually dont care about bank letter or statements because of that, but they did ask once, to see that the money actually gets transferred in.