It wasn't only the inbound flight that had a problem. Our plane on the outbound leg had to be replaced too.
We were scheduled to fly out on a 737 and passengers were checked in at Newcastle using the 737 seating configuration i.e. three seats a,b,c the aisle and then three seats d,e,f. The plane we got was an old MD83 which has two seats a,b the aisle and then three seats d,e,f. We had seats 2a,2b,2c which we had paid for to pre book seats together. Seat 2b did not exist which lead to a free for all, just sit anywhere policy. The less said about the state of the plane the better.
The most annoying thing about being flown to Glasgow is that Excel knew hours before we boarded the plane at Fuerteventura that they were going to fly us to Glasgow. They just chose not to tell us until we were on the plane, and cabin doors locked. Very cowardly indeed.
Excel in my experience are just an awful, awful airline and don't deserve any of our hard earned cash. They certainly won't get any more of mine.
I have posted a full review of my experience on the Flight Only discussion section.