Can I reduce my bank balance to 400k after showing 800k for my Non-O visa extension in Thailand?

Can I just check this is all ok please, did Non O extension 3 months ago, all legit with 800k etc, went yesterday to show the 800k maintained for 3 months from extension

I also started paying over 65k a month in even before the extension

I want to renew next year on basis of 65k

So can I now reduce to 400k for rest of this year and continue monthly payments ready for next extension? Also if I do this was down I have to put back to 800k for last 2 months of year or is that not needed if switching to monthly?

Once I have switched to monthly can I then reduce my account further with no minimum balance as long as I continue my monthly payments?

Thanks in advance