Last year, I went with someone to Chaengwattana Immigrations in Bangkok who held an OX visa so they could see what the requirements for the extension were.
They were told by the immigration person either go back to their country and get a NEW Non-OX visa or just go thru the BOI and get a Long Term Residence (LTR) visa because they had never ever extended an OX visa inside the country and this was at the main immigration office in Bangkok ๐ฎ ๐
I concur with that advice and I would say either go back to the US and get a new OX visa to get 5 years again OR apply for an LTR visa thru the BOI website under the 'wealthy pensioner' category.
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