As a general rule there is no onward travel requirement at IT Square Laksi Plaza to get a 30 day extension on a visa exempt entry.
In Bangkok you do not go to the the main immigration office at the government complex on Chaengwattana Road for a 30 day extension on a visa exempt entry
You go to IT Square Laksi Plaza 3rd floor (there are copy/photo shops on either side of the immigration office there)
This is where it is (about 2km from the main immigration office)
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