Originally Posted by
craigthemif
Although self-re-routing makes total sense for those able to do so, I would assume that IB will treat you as a no-show and will deny all refund / compensation claims.
At which point you will have to take them to small claims court. Since presumably your direct flight will arrive earlier than your LIS-MAD-LHR route, you'd only be looking for a refund of either the unused IB ticket or the Avios for the replacement.
Looks like IB3103 was actually cancelled, but perhaps after OP had already departed LIS on BA. Does the timing matter? Ie OP can only claim the self reroute costs (and not go for refund) if they had booked it after the flight was cancelled? Or if by LIS-MAD being delayed (but not even by a lot) but then making last same night MAD-LHR impossible, and the gate agent refusing to rebook, is enough mandate for OP to self reroute and get refunded for it? Good (silver lining for OP) that the fliht was actually cancelled though and not OP being a no-show.