I wasn’t able to call until a little while ago, and I found out that we have to be in our 60-day ADR window to book. Since we want the December 16 show, we’re in great shape, because I also found out that the December 9 show sold out in about an hour. I’ll be calling promptly at 9 AM Eastern when our window opens in a couple of days!
The CM at guest services did give me a confirmation number, and I assumed that I'd have to enter into MDE or online on the website for "My Plans." When I opened the page (immediately after hanging up with DVC), the HDD was already there in "My Plans" on 12/9.
An interesting thing was that the CM told me that I would have to show photo ID and my DVC membership card when checking in. I guess they don’t want any "scalpers" at this event!