High school years- event stops Sims from being able to attend classes on time

Since the update that changed the high school day to an event I have experienced the following issues; the event does not show up for more than one teen, I no longer know what time anything is and my teens are constantly late to lessons, increased difficulty on making my teens a good or bad student as there are no continuous tasks throughout the school day. Tasks show they are completed when they haven't been and incomplete when they have been completed, no school day event shows when there is a holiday event already on.