First off, let me say this site is the best guild site system I've found for pre-made guild sites.
I plan on using the Raid Availability module for our guild. On our old site, we had an attendance thread to indicate when someone could not make a raid. We are a fairly hardcore guild so attendance is expected unless you've posted. Is there a way of adding a "Not Available" checkbox so you can see people who can't attend for an evening?
One of the feature coming rather soon is the ability to default a certain list of people to sign-ups, and then have those members who can't attend manually retract their signups.
Similarly (and currently available), one can simply utilize the signup system for it, and have those members sign up for raids, or choose to state they are unable to attend those events.
The Raid Availability is primarily for general planning, rather than more specific planning, though the idea of inserting "anomolies" into the Raid Availability does present an interesting tweak.
