I'll second autoflights point. It's very annoying to be told that someone cannot make their slot time 10 or 20 minutes after the event (sometimes as much as an hour goes by without anyone thinking of telling us).
All this means is that a slot is wasted and the flight concerned ends up queing up behind itself!
If a missed slot can be given to somebody else, often the flight that missed the slot can be given the newly vacant slot of the improved flight. Then everybody's happy.
