User blog comment:Dopp/Technical Update: November 15, 2011/@comment-3569803-20111115211100/@comment-1656630-20111116194925

That one's known, too. We had to reset a database staffy-testing thing last week, which gave all notifications from before that date a lifespan of one week. It was just a one-time thing, though. The joys of being in early testing mode. Sorry about that.