Funny, when I did my check-in some days ago with QATAR, the Agent wanted to see my TDAC Form. I told her that, just in case I would not have one, I can use kiosks at BKK to fill them in. She did not know that, but told me she has to check the form anyway. Did not ask what would happen if I had no form.
Immigration was a breeze, less then 5 min. Followed by 30 min. waiting for luggage. The joy of arriving with a, filled to the last seat, A380.