When is the best time to apply for a 30-day extension to a SETV (60-day tourist visa)?

The best time to apply for a 30-day extension to a SETV (60-day tourist visa) varies by immigration office. Most offices allow applications when there are 30 days or less remaining on the visa, while some may accept applications with up to 45 days left. Notably, the Jomtien office advises applicants to return only when one week is left on their current stamp.