What it means is that though it's multiplayer, not everyone needs to be on at the same time. It's 'stamina' based turns. You have a daily stamina pool, and each day that pool replenishes, so you get X number of points. Most people it seems this takes 20-30 minutes a set (from what I'm gathering) so you wouldn't just sit there and play the game all day. That's in normal mode, anyway.
In Blitz mode, game days take 15 minutes (vs 1 RL day in standard mode).
