Flying from Heathrow today to Bahrain and then on to Bangkok via Gulf Air.
I would recommend getting to check in early (we got here 3.5 hours before flight) as it took us over 1 hour to check in.
PRINT OFF EVERYTHING!
There was no checking of anything on mobile , everything was paper checked - RT-PCR (Make sure this has your correct passport number), Covid certificates, Thailand Pass etc.
Good luck!