I would keep checking flight availability to newcastle if you are at LHR or see about standby? I have been automatically booked onto a flight later today which I wont be taking but cant get through to let them know yet. I assume that lots of people are like this. I know when we were told we coudlnt fit on an LBA flight a couple of years ago and rebooked for the next day I held my ground (albeit in the CCR) and waited at the airport and the flight ended up less than a third full as those with connections couldn't get to LHR to catch the LBA flight.,