User blog comment:Jyggalag Daedric Prince of Order/Season 9 A Bust?/@comment-24303436-20130531030550/@comment-3045936-20130531053115

It's possible but two factors prevent them from just doing anything they want. One, for the sake of series story. If the story doesn't flow with the series, it loses ratings. The second one, is actors. Not every actor can/will/ is able to just return for their roles in earlier seasons. Now a supernatural series like this one, allows more freedom. Like with the blonde two to the brown haired Ruby. But, they cannot do that for everyone in a realistic manner.