I was aware of the pitfalls of taking the train. I do like riding in trains and was on the Budapest to Berlin overnite train 1 month before the migrant crisis in Europe. My intention was to fly 1 way and train the other way. If train times are not reliable, would a flight from Chiang Mai to BKK airport (several at 6-7 am) connecting to that 9:50 am JAL flight be OK?