Why did my due date change?

CMC has a set due date for the return of textbooks. This date is advertised all around campus, via email reminders to CMC email address, via text and is given out by course instructors. Once that date has passed, the student has 2 weeks in which they can return the materials but will be charged a 25% late fee. Once the two-week window has expired, the student now owns the book.