I see from the Phuket Immigration Volunteers site (which is usually reliable) that you can apply for the retirement extension 30 days before expiration. I may have just been lucky when they accepted my application more than 30 days before expiration. It may actually depend on how busy they are. If you show up 45 days before expiration and they are not busy they might just figure, why not, and accept it from you at that time. Worst case they say, too early, and you come back 30 days before expiration. Of course, you would need new bank letter and stamped bank statement if they turned you away.
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