Interetsingly (or not as the case maybe) I was flying back from STR-LHR last week, and received a text on Tuesday night (return flight on Friday) saying my flight had been cancelled and that was that. Anyway logged into said companies web site the next day, and my flight had indeed been cancelled. I would have thought that I would have been auto booked onto the next flight, but I had to call in to re-arrange which wasn'y a problem.
Anyway, the point is how would they know so far in advance to cancel the flight? - loading, misplaced an aircraft?