Bit of a speculative claim here...
Was booked on BA188 (EWR-LHR, departs 21:25) back in 2012 which was cancelled. I was rebooked same day onto BA184 (EWR-LHR, departs 18:25).
Obviously I was not delayed per-say, but inconvenienced by being rebooked onto the flight at 18:25 which was 3 hours earlier having to cut my trip slightly short.
I think the reason for the delay was mechanical, but in reality I don't really remember.
Am I able to make a claim?