I feel your pain having experienced it myself. I went through EDI late last year and missed my BE flight back to BHX by milliseconds despite doing the 'Home Alone style run' to the gate, they had literally just closed the gate.
Now most people would say "you should have got there earlier" etc blah etc but I joined the security queue with over 50 minutes until dep time and still never made it.
Had to go back to check-in and the lovely member of staff shouted to her colleague "we've got another one, security is shocking today". Thankfully it wasn't the last flight of the day and they didn't charge me to switch, gave me a lounge pass and free fast track.
They actually had security go back and track me through CCTV to make sure I wasn't fibbing and my story checked out, I think it was something like 51 minutes from joining the queue to getting out the other side. It wasn't even remotely busy hence my choice not to fast track but I was far too committed to turn around and chance leaving the queue.
Flybe logged a formal complaint and so did I. Still waiting for a response
