What is the "free domestic add-on flight with BA" ?
How does that work ?
well before the devaluation, any flight in and out of london was entitled to a free stopover in london and a trailing (or preceding) flight to anywhere in the UK for no additional avios. now its limited to long haul flights only. for example, i booked FRA-LHR on 7/5 and then LCY-EDI on 7/27, for a total for 4.5k