My friend has a 30 day overstay on a tourist visa due to a combination of dengue fever and a scooter accident. She does not have a hospital certificate. Would it be better for her to go to samui immigration to pay the overstay fine, and apply for a retroactive 30 day extension (she was too sick to go to samui for her extension before) Or should she just book a flight out of the country tomorrow and pay the fee at the border. Is there a chance she would not be allowed back in after a 30 day overstay?