Emails about outdated author events

This morning, I received 7 email notifications of author events in my area. They were all for authors I followed, but they were all for events in the past (Nov 2008 - May 2009). These were not duplicates — I had never received any email notifications for these events. I looked back in my email archives (thanks to Gmail) and I saw that the most recent author event notification email I received before today was from 5/2008.

Perhaps a mail queue that had been backed up was cleared out?