So, as of about 10:00 AM today, the prophecy.dkpsystem.com site is, from what I could tell, no longer reserved (The old owners, whose guild fell apart early last year, did not resubscribe, and the grace period posted at that URL expired). However, when I try to change my domain to that, I am told that the subdomain is not available.

When do expired names become available again?

The subdomain is freed now.

At current, there is a manual authorization step to free the domains.

Thanks. I was worried a site policy of some sort was going to make a liar out of me hehe.