I've been told by the BEA admins that someone is working on the site, and to be patient. Nothing more than that. I asked for an ETA but they didn't answer that.
All the site files, including all the episodes, are still there. It's just that the URL forwarding for the Addventure (and the Forum too) is broken. I can still log into the server and access the files.
This seems to happen every time they decide to tinker with the site configuration.
Sorry for the troubles, but it's out of my hands.