Very happy to report that things are same same at Bumrungrad Hospital. I just extended my tourist stay there. All one needs to do that is passport, departure card, and 3000 baht. You make an appointment during the week, and then show up Saturday morning where a few immigration officers are there to finalise things. Money well spent! And the perfect excuse for an early beer and rejoice about NOT going to Chaenwattana :)
No TM30 nonsense, btw.
And contrary to what it says on the link, you do not need to be a patient to do this.
Oh! And you can also do 90 day reporting in a similar manner. I don't know specifics about that. But I'd most certainly look into it if I were on a relevant visa.
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