What is the process for arriving in Thailand during the new immigration rules?

Just under the wire!!

Landed at Swampy tonight (21st) just before the new rules start. Booked the VIP FastTrack, more for the convenience than the wait. After landing, somewhere before immigration, everyone was funneled through thermal imaging. Several meters later everyone is funneled into 3 lanes to download the AOT app for self reporting. I had already done that, filled in my t8, and gotten my Barcode so we went around the huddle, showed my bar code, got a stamp and headed for immigration. Officers wanted to see the aot stamp and Barcode before I could go to immigration.

At immigration there was zero mention of a medical certificate, self reporting, or insurance. The only question asked was "why are you here? this line is for business class". My fast track guy waved and I was stamped in. Since I had the app thing done, it took about the same time as any other trip. Airport did have more arriving passengers than I expected.