Aircraft swaps would never put me off applying for a job just so much better when planned well.
I have just had bad previous experience with another employer who would quite regular plan these and know before you have even left the UK that the aircraft they want to swap and for you to bring back to UK has a couple of hours delay on it and can assure you not much fun waiting around on the ground waiting for your inbound aircraft when you should be nearly home.
I am pleased to hear that this does not seem to be the case with Thomson and things look rather positive