The issue is with all the lockdown restrictions it's more likely than ever that you will be caught on overstay away from the airport / border (for example at a roadblock checkpoint) and then you will be deported and blacklisted for 5 years.

@Gary *******

a "lawyer" with some connections i presume

Probably within a couple of days most airlines will cancel flights for the foreseable future and more embassies will start providing their citizens with the letter to prove you can't leave to get an extension.

maybe better you go to chaeng wattana on monday (or later if you still have time left on your stamp) because it's likely most outward flights will be cancelled very soon once the airlines realize the only way to get their planes here is to fly in without any passengers, then immigration will have to come up with a solution (and/or the british embassy will start giving those letters).

Bit late now. I saw Chinese checking into flights at BKK with trolleys piled high with boxes of masks as early as December, and the Thai government has been encouraging huge wastage of masks by healthy people over the last 2 months, in contradiction to advice from the WHO. Now stocks are running low for people who really need them (for reasons completely unrelated to the hysteria around covid19).

I had a similar thing but just 1 month wrong. I didn't realize until the last day of the stamped date (when I was 30 days overstay in the system) and had to drive half way across the country through the night to the office that made the mistake to get it fixed (apparently it was impossible for any other office to amend it).

if you've made any thai friends over the last decade, try bringing one of them back with you for a holiday to the uk and see how that process compares to your experience.

sounds like you've been in thailand for somewhere around half the time in the last decade. doesn't seem unreasonable for the immigration officers to check if you are really a tourist (all the questions they asked were very relevant to that judgement).

assuming you are not planning to die in the kingdom, you could buy a flexible return ticket and/or cheap throwaway onward ticket. or you could just show up at the airport 30 minutes early so you have extra time to book the other flight online if the ground-staff wont check you in.

I had an issue where one border officer made a mistake with the stamp in my passport, which didn't match my record in the system (which was noticed by another immigration office). I had to drive half way across the country to the original office to fix it. It seems although the system is connected nationally, each office only has access to edit some parts and there's still some human input and humans make mistakes.