If you have multiple divisions and a team drops out or joins at the last minute, after you've already sent out the schedule, and removing/adding their games manually is going to be too much work, you have the option to regenerate only that division.
You can regenerate one division's schedule while keeping all other divisions' games exactly as they are by clicking the regenerate division button next to the the pertinent division:
This will only use the timeslots already used by that division as well as any unused timeslots.
This will delete all games in that division – including those already played – and create new ones. You cannot currently regenerate only future games. We're hoping to add this functionality soon.