My friend did his about two months ago, mine was about five months ago. It is necessary to explain to section C staff what you intend to do. Initially with mine they said I would need 800k because that's how that section is programmed, so the supervisor went to the section which deals with the 12-month extensions to get the nod, so it is necessary to be a little affirmative.
Correct. My non-OA extension lapsed whilst I was out of the country and I came back in on a visa exempt and applied for the 90-day non-O off that, but I kept the 65k transfers going the whole time. For some reason, section C wanted to see proof of my Australian pension (not supported by affidavit of course as this is not available for Australians). A friend of mine who did the same process a couple of months after me, and for his they wanted the actual foreign transfer receipts from Bangkok Bank (which the branch at CW were able to supply). This was in addition to the twelve month statement and updated bank book
If you apply for the non-O in Bangkok, showing the proof of at least 12 months of 65k transfers without a break, yes you can do it. Speaking from experience. Go to Section C at Chaengwattana. They might ask for individual FET paperwork from your Thai bank, so check first. I emphasise this is Bangkok only