My IO have made it quite clear that I must re register tm30 each time I return home after only one night away at another address. I now do it on line. In addition if you file 90 day report on line and your current tm30 does not match the home address it will be rejected. I always file tm30 on line just before 90 day report just to be certain all matches up and do not have any issues. .
and if he is not tax resident in Thailand in any year income received in that year is not taxable when remitted to Thailand. Ie pension payments and anything else earned. Not sure if pension payments are taxable or not.
It is possible you could still apply for the retirement extension if your funds were at
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0 baht for 3 months after you got the last one and you can top it back up 3 months before applying for the best one. The requirement is that your funds do not go below
the answer to 1, 2 and 3 is everyone unless they like getting run over by a bus, like the sight of their own blood or enjoy seeing little children battered. Your last sentence is quite odd because you must be the only person who is hoping to pay millions of baht in tax.
On a slightly different tack Thai revenue are soon going to work out that it is not cost effective to go through your tax affairs only to find out that you might just owe them 1 to 2 thousand baht.