I have read in many places, including here, that when I return from a vacation, with a multiply entry permit, and having a Non-O retirement set- up, that I don't need to report to immigration on my return.

Last year I did this, and did not go to immigration until my next 90 day. I was fined 800 THb for not coming the next day to immigration to tell them I was back.

Was this a fluke, or what? Korat immigration.

Thanks.