Well Dad has had many of these happen.

Once when flying to France to visit my sister we were delayed by a meeting that some idiot at his office scheduled without checking if he was busy. As we were going to miss our existing flights and he didn't want to fly on his own we were all then flying Crossair from LCY at the companys expense ^ .

Whilst skiing in France he had to come back to the UK for a day, and attend a meeting, which meant sending a plane to meet him at CMF (Chambery) and fly back as there wasn't a scheduled service to Glasgow.

In ACK one year he knew there was a chance that he would be coming back, and thengot a message saying that he was needed in London. Cunning plans abounded as he decided to do an overnight back to LHR, and do whatever it was in the morning/early PM and then get Concorde back to JFK, total loss of holiday 1 day-ish. Then his PA discovered that BA had cancelled the PM Concorde for the summer (I think, may just have been a month) and he had to do it the slow way.

Several times to NYC from ACK/BOS, which isn't so bad in the grand scheme of things.

When I'm away, I either don't tell work what the number is where I am, or I leave it, with a note saying if they have to call me I'm taking an extra days holiday. Thanks to this they've never called, and I don't do mobiles so they can't get me on one of those.