Ah ETOPS, thanks for the explination, it is something that has troubled me for years
They used 1-11s as back ups to Glasgow as well but having any old aeroplane hanging around an airport was quite useful. One of my first fam flights (remember them???) was a hop to Aberdeen. Unfortunately, the Budgie was bust so they used the Trident that was there as the shuttle back up. It took about 20 minutes.
