Interesting thread to read. When I was there in December, the only place I was told I couldn't enter without a pre-booked ATK that I didn't have was the new year party at the Hyatt Regency. And temperature check stations were at hotels, but it was about 50% of them that actually checked, mostly checked when entering malls. Good to see things have cleared up before my trip next week though.
One question though, for check in on domestic flights (DMK-CXN/Chiang Mai), are there any requirements I'll need to board at this point?