A 3 hour delay last year with Flyjet trying to do MAN-HER.
No reason was given, but I presumeed it was because they had to source an aircraft, or to put it differently they had no aircraft to operate the flight.
In the end we were put on a Finnair B752 OH-LBS, operating for Air Scandic who were operating for Flyjet! 🙂 To put the icing on the cake there was no food for the whole flight except those pitiful little rolls you get normally with the hot meal.