Just an update for Udon Immigration. All smooth and efficient as usual. I did a TM30 as I was also getting a notification of residence for a driving licence. I specifically asked do I need to do a TM30 everytime I leave and re-enter Thailand or stay elsewhere and return back to Udon. They said no problem, just do a TM30 if I change address and that's all. No need to come back everytime.