Obviously like many here I having been following this thread with great interest. Many of those posting on here know far more about the topic than I do.
However, I had the good fortune to talk directly to the Flight Ops director of a major UK airline a few weeks ago, who assured me that even in the event of a hard Brexit, on March 29th they can keep operating.
they base that belief on the assurances that the CAA will continue to recognise all UK licences and approvals issued under the umbrella of EASA as still being valid to operate G ref aircraft, and that ICAO third and fourt freedom rights will still exist between the UK and individual European nations which are still ICAO members regardless of EASA.
Im sure they have taken a huge amount of alegal advice before deciding this to be the case, so whilst I can see easy jet and Ryan air having a problem, what is the issue for UK based operators of UK registered aircraft operating out and back flights to Europe with no intermediate sectors?