this is Thailand so Defined fully doesn’t really apply but if you want to know as precisely as possible, contact a Visa Service, they’ll know as precisely as the governmental changes allow.
Whenever you enter/re-enter Thailand you get a stamp on your passport. This new stamp is for a two month visa (tourist) and this same new stamp cancels any visas you had before UNLESS you got a re-entry certificate from the Thai immigration before leaving Thailand.
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