all you need to do is cancel your ED visa and exit Thailand. Enter visa-exempt (or with a 60-days tourist visa aquired abroad) , and apply immediately for a "change of visa type" from the "exempt entry" to a "90-days Non-Imm-O retirement visa" on Immigration. you must proof that the 800,000.- THB on your account came from abroad. . .here are the relevant requirements . . click on number 9 for your situation
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