Sign up for Touring Plans Reservation Finder, and have them alert you by TEXT. Then keep your text on loud so that you hear it every single time it beeps. I have found this to be the most effective way to get an ADR that I want. It's much easier than haunting the
MDE website and more efficient and effective.
Good luck!
ETA: sometimes the texts come in very late at night, which is why I say to keep your sound on loud!