A few will be there early helping the setting up, a few will arrive later to argue they've done it wrong, a few more a bit later to flounce off and set their own tents up and ignore everyone, and yet more will arrive in the dark, fall over the early birds and moan they haven't got 'last years pitch', but by the evening we'll mostly be having a beer or three together and laughing at each others poor dancing skills ...
Or similar ...
Arrive sometime friday afternoon/evening onwards .... leave late Sunday/early Monday .. ish ...