Some time before we have discussed that people sometimes are playing their games although they have vacation days. Now I have seen this issue at another chessserver.

If a player wants to make a move during his vacation days a message appears:
"You are in vacation at the moment,and if you make a move the vacation is finished automatically".

But if the vacation days are finished the time runs again for all the games of the player.
So it could be prevented,that people take their vacation days only to extend the time for some of their games.