OP, here is a random thread.
https://aseannow.com/topic/1319982-retirement-extension-jomtien-trip-report/
Don't bother with it apart from
OP report. Here is a snip from it.
"Then I will also see if I get the form to return in three months to show the 800K still in the bank. For me it varies; Some years I do get it and some years I don't. I never bother to go back anyway, I think it is meant more as a reminder to us than to them"
Have read MANY reports of folk ignoring the "return with bank book" in 3 months.
I have NEVER read a report where failure to do so resulted in issue with next extension.