If you explain you're going from chiang mai to phuket to the officer THEY will tell you what to do. You'll also save yourself hours IN the office doing it in chiang mai and not phuket (besides the drive back and forth). Why not ask those who can solve your issue (immigration officer) to help instead of asking all of us to play multiple choice all based on "what ifs"???? I promise that every single day then encounter your exact situation multiple times. Their clients are tourists and tourists TOUR lol