Visa Question: I have a passport from the USA. I flew into BKK, from the U.S, on December 4th, and got a 30 days Visa on arrival. Flew out of BKK to Siem Reap Cambodia on January 3rd. If I take a BUS back to Bangkok on January 18th, can I get a 30 days stamp, plus do a another 30 days extension for a total of 60 days this time?