Extending single entry tourist visa. We entered Thailand and our 60 days expire February 15. We plan on extending for the additional 30 days. We've received contradictory information 1) wait until closer till our original expiry, no more then 3 days prior 2) we can do this at anytime prior to expiry. Which is correct? We plan on spending a lot of time on the Andaman side which don't have an immigration office so would like to get the process completed in January while in Bangkok and Chiang Mai. Thanks!