BA and EZ will both lie to you initially. Faced with facts and an impending CEDR or MCOL, BA will cave in quite quickly and pay. EZ will only pay when they get to the steps of the county court. Be prepared for hassle but stick to your guns and you will win. The excellent EU261 thread on here is a long read but interesting, educational and enlightening. Read it so that you don't make some of the schoolboy errors we have made and you will get your out of pocket expenses plus GBP 2,800 in total compensation.

Incidentally, Miss Tafflyer is taking EZ to court in Germany for a cancelled LGW-MUC last year. They lost the initial hearing but appealed to a higher court. Having filed counter-suit for additional related expenses, they now want to settle without prejudice, but since the court where their appeal will be heard would form precedence in the issue of failing to reroute on other Airlines, I am going to follow it through. You reap what you sow.