Hello,
If you go to immigration in Chiang Mai and apply for an extension of a 30-day visa exemption, what happens if they've not made a decision by the time you leave? Also, if they do make a decision and grant you the extension, do you absolutely have to go back to immigration, or can you just show at the airport that the extension was granted?
Many thanks in advance.
TLDR : Answer Summary
If you apply for an extension of a 30-day visa exemption at immigration in Chiang Mai, you will receive the extension stamp on the same day. If you leave Thailand before a decision is made, it's important to note that you'll still possess the extension stamp for your departure, which can be shown at airport passport control.