Here's a list of my check-in experiences around Europe and UK.
I travel in uniform as I travel for work. I carry all the paperwork etc.
I am a Brit that's double jabbed and got a PCR test for Portugal.
Day 1. LHR-GVA, Swiss Airlines.
"Have you done the Swiss PLF and can you show me?"
"Have you got proof of double jabs?"
yes to both.
"Great, here's your boarding pass"
Day 3 FCO-LPT, TAP
"Have you got proof of a double jab or PCR?
"Have you done the PT PLF?"
Yes to all 3, happy with the PCR test. (I got one done, "just in case")
"Great, here's your boarding pass.
Day 7 LPT-LHR BA
"I need your PLF"
"Where's your PCR and post flight test bookings?"
I am exempt, I don't need them to travel, but here's my PLF.
"you're not exempt, you need a PCR. I need to see your roster"
I am exempt, I am not with BA, please speak to your manager (Having witnessed the check in person be just as rude and abrupt to a dead heading BA captain.)
"Wait over there, I need to speak with my supervisor"
Cue deep breathing.
Riiiiiing. Short phone call later.
"ah Ms reddo, please come forward, all sorted, you are exempt, you may travel, here's your boarding card"
I caught up with the BA pilot later, he was shocked at how rude she was and we shared what happened. Eerily similar.