I am travelling northern Thailand in July with a Thai friend who needs to get back to work by the 24th, so I was going to buy him a seat on a domestic out of Chiang Rai to Bangkok on the 23rd. As I am out of the country, I am guessing he will have to buy the ticket himself given ID, Thai name etc. I know nothing about domestic flights in Thailand - their reliability in terms of last minute cancellations or how heavily booked they will be at that time of year. Looking for some advice.