The following message was posted on the main University of Toronto Libraries web page on October 26, 2009 and may be applicable to you:
Overdue notices sent in error
Due to an error, some incorrect first overdue notices were emailed to library users this morning. If you received an overdue notice for a book which is not due yet, please disregard the notice.
We’re taking steps to prevent this from happening again, and we’re sorry for this error and the inconvenience it has caused you.