Thanks RJ100
My son has been talking to BA today to see if they would switch his booking Aberdeen to LHR to Gatwick; there were still seats available for the 23rd on several flights.
BA's response, no we can't switch you to another flight during the strike period but you can re-book a flight after the strike is over. This is of no use so my son then asked for a refund. Sorry no refund possible untill the flight has been oficially cancelled. On the BA website they state that they will do everything they can to assist passangers; my son's experience says otherwise. I can't see BA surviving this debacle even if its called off at the last moment.