Originally Posted by
SWBKCB
Quite often it can be because you just don't know - delays can be very fluid situations, and Murphy's law is quite often in full swing. I've worked flights (in the dim and distant past) where the departure/arrival time of a flight has changed every five minutes for different reasons.
And if the airport doesn't know, it's because the airline (or their agent!) hasn't told them.
re DUS - is it not just changing from a LH to an EWG base, so not much impact?
But they will know the basic reason, ie bad weather elsewhere and don't know when it will improve, and passengers will accept this and know it is out of the airport's/airline's control.