You could apply an extention stay or a re-entry permit at every checkpoint.
—
For a re-entry permit,if you are in Bangkok area and you have an Internet access, you could
fill in a TM.
8 form and send it to bkk1_reentry@immigration.go.th
—
You should e-mail the completed form 1 day in advance.
—
You have to submit a 2" photo and pay a permit fee at counter 7, the Immigration Bureau (soi suanplu office.)
—
Fee for re-entry permit:
1,000 Bahts for single
3,800 Bahts for multiple
With c ooperation between Immigration Bureau and Government Contact Center, now you can call 1111 for immigration inquiry for 24 hours. 3 baht per call for fixed line phone.