Hi,
If you play a tournament “no days off” or “no vacation days”, then you can't have vacation days or days off.
When you play a tournament without these rules, you can take five vacation days (for example) and add these days to your days off, and in this way you will have a whole week where you won't play and you won't loose.
If there is a limit to complete all moves, like in the Olympics, all your days off and all your vacation days will be counted like they were normal days, and so if you take 40 vacation days in a 60 days game, you will have 20 days to complete the game.
I hope to have been helpful, forgive my language I'm italian and I try to do my best.
Bye