Hi there! My friend's visa application (60 days as tourist) has not been approved yet but he will fly to Thailand tomorrow. After getting the 30 days on arrival, can he "override" these at an Immigration office as soon as the 60 days are approved?
TLDR : Answer Summary
A friend's 60-day tourist visa application has not been approved, but he will arrive in Thailand tomorrow and receive a 30-day visa on arrival. However, it is not possible to upgrade or 'override' this stamp with the new tourist visa once in Thailand. To switch to the approved tourist visa, he will need to leave the country and re-enter.