When i was hour building and gaining my PPL in FL I went over 3 times and actually made a profit on the air fares as well as flying for free.
All 3 times on the way back I accepted changes in travel plans and was awarded more than I payed in the first place. Plus 2 nights in nice hotels.
Once I actually ended up where I wanted before I was due to get there by the planned route, and it managed to miss out Heathrow which I would have payed extra to avoid.
MJ