Unscheduled Server Maintenance

I think it would be more fun say if they brought down only half of the chs to SC and then vise-versa.

Most SC's aren't about the individual channels - They're so all players are offline so they can do things like world transfers and name changes, and disk cleanup and database optimization. All things they can't do while the players are actively accessing their files.

For the ones that are about the channels, it's just easier to take everything down together and bring it back up together, that way you don't have to take anything back down if you discover further complications and have to restart. It also ensures noone gets lost on which ones are done vs which ones still need doing.