Love the repeating unavailability feature that has just been brought live. However, it would be good if it could also allow volunteers to specify unavailability for X week of the month (1st, 2nd etc.). We have a few volunteers who have a commitment elsewhere on the 3rd Sunday of each month, and it would be good to enter them as unavailable for each of those weeks at once, rather than have to use the less clear volunteer preferences approach or enter each month separately.
At this point if it's going to be every 3rd Sunday I'd suggest getting them to use the Preferences option instead, simply because it doesn't require them to set an End date.
There is a request for some more flexibility with the repeating schedules though and I'll your support to that request.