You can book and appointment, show up 15 minutes before with all the copies, forms etc you need and get seen right away OR you can queue up with the zombie horde.
Keep in mind next week immigrations in Bangkok is closed Wed, Thurz, Fri, so if you're going this comin' week you need to do it Mon or Tues.
Sadly, if you queue up without an appt it takes as long as it takes, although as a rule Tues-Wed-Thurs are better than Mondayz or Fridayz,
The 30 day extension is ADDED to your current expiration date so you don't lose any days going before the current stamp expires.
Here's the link to make an appointment for Counter J
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