Or, similar to what we see now when we completely delete a snow date, we just wouldn't see anything in the grids for that week. (Any query for getting session dates would just have to add a check for the canceled = True) I guess the only difference from totally deleting the date would be that we'd have a record of the date in the calendar saying it was canceled.
On the other hand, we could just add a note in our Home page's note tab saying the same thing!
So, I'm not trying to convince you to implement it, just throwing it out there, since the question of how to handle a club cancellation has come up several times. It would probably be more intuitive for users to have some kind of "Club Cancelled" button. But still, may not be worth it.