I think (and this is pure speculation on my part) that it seems only logical that sometime soon the special edition will make it to the 30'. I say this because I've seen lots of neat things Airstream is doing on this last trip out there. I recall when someone asked for a 19' Special Edition, the answer was no, but then a few months after the 25' was out, here was the 19' Bambi Special Edition.
I also seem to recall a comment made that did not directly say it would happen, but that folks were looking at how popular the other models did before rolling it out...meaning it could happen, it could not happen. Take it a face value.