If a reading day is scheduled before the last day of class, instead of studying for exams, many students will find themselves working on final projects. Most courses have cumulative final exams. Using a Saturday as a reading day does nothing but delete one day of possible preparation time. But since not all students had an exam on the first Saturday, this justification is not enough. When C.D. Spangler, former UNC-system president, proposed the longer semester, he did not mandate that more academic days must fit within the confines of previous semester schedules.
Some days have a generally-fixed formula.
Through the years, the last day to drop or add classes has not varied much. Some observed holidays, like Thanksgiving, always fall on same weekday and involve minimal shift in date. But in order to have a well-planned ending, many students would accept beginning the semester one day earlier. The Calendar Committee might more effectively plan a semester starting at the end and working to the beginning. Using Friday as the last day of classes would free Monday and Tuesday, then exams could run Wednesday through Saturday and Monday through Wednesday.