a further update:
Monarch airlines then managed to find a replacement aircraft, an airbus 321, which unfortunately had 5 fewer seats, so some unfortunate passengers were left behind...as was some of our luggage. In the meantime we were told that the 757 had suffered engine failure...
Gorter - an easy assumption to make if you are a slf and seem to be spending longer than expected over the sea. I have quoted directly to provide some answers to the original question posed.