What are the exact requirements for the Non-O visa extension in Thailand after meeting the financial threshold?

Exact requirement for non-O

Sorry, would like to continue my older, related thread but can’t find it. I just got my 12 months extension for my visa. Apparently I matched the financial requirements by having 800000 on my bank for 3 months. I am supposed to keep 400000 and 2 months before I need to extend again it must be 800K again. Now these are the requirements for the NEXT extension, is that correct? I have already matched the requirements for the last extension. I want to understand 100% what this requirement really is.

I plan to extend or reapply based on the 65K per month and in that case why would I need to put 800K again? But if this is for a future extension then aren’t the 400K too? And could I just take that money if I was to reapply with 65K/month?

Sorry if I am a bit annoying but I am also doing a BOI next month and the amount of money to keep on banks gets ridiculous. And if I am done with the BOI company then I wouldn’t reapply for non-O at all...