Same happened to me, it's been a very stressful 6 months since my partner qualified for SP & I was moved to UC. I too had to attend JC work coach meetings, I found myself in an odd situation where my ID was checked by a SA job coach thinking it was a fraudulent passport!! I've never used it to fly anywhere, just for ID purposes in the UK. I sat there for 45 mins wondering what was going on as she phoned a gov legal dept. It was humiliating and unnecessary.
It may take a few months to get your UC claim established. Keep all your medical info in a file when you go to the DWP/JC, show the Job coach. There are guides here so go for the UC one, it explains a lot. Hopefully, in a few months, your UC claim will be settled.
