#1 - Sept. 18, 2010, 11:12 p.m.
Blizzard Post
The Challenger title, Stetsun, is only meant to be kept for one season after you have earned it. It's possible that if you continued participation and earned it each season, you had kept it up until now. But these titles are meant to be removed each season from those who had earned it previously (unless they reached that status again).

I understand that may be confusing, but I hope I've clarified that a bit. In addition, I believe the forum you may have been looking for regarding this issue would be our PvP Forum, and the FAQ in question would be our Arena Rewards FAQ.

Arena Rewards FAQ
http://forums.worldofwarcraft.com/thread.html?topicId=22418638782&sid=1