Sheesh, you got some good and some total shit answers on here. MOST posters correctly pointed out that you can apply for a new yearly extension of stay at the immigration office in Jomtien when you have 45 days or less left on your current stamp.
There is no up side to waiting until your current stamp is running out, you don't lose any time on your extension going early, they ADD the new year extension to your current expiration date..
Keep in mind for the funds seasoning using banked money it needs to be in the bank 2 months before you APPLY for your next extension (not from when your current one runs out) :)
@Mar****
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@B*
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@Te***
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@St***
got it right (y) (y) (y)