Every previous trip I've gone through immigration at the airport I landed at. And leaving I've gone through at BKK. This time leaving I went through immigration at Chiang Rai even though I connected at BKK... And my bags were checked all the way through where previously I've had to collect and recheck in BKK. Now, returning, my bags are checked all the way to Chiang Rai. Do you think I will do immigration in BKK or CR?