On the surface, it doesn't. BUT understand that in many cases you have to book a holiday cruise more than a year ahead of time. How many schools, especially ones that decide on a whim to change from a 5 day week to a 4 day week, know what the calendar is going to be 18 months ahead of time? My district once started the fall semester without a master schedule...4 days where the students had to be there...but had nowhere to go!