Only works if everybody agrees on which day is the '5th' day. My wife has chose to work 4 days a week (80%) and she has to constantly fight to keep her free day

Only works if everybody agrees on which day is the '5th' day. My wife has chose to work 4 days a week (80%) and she has to constantly fight to keep her free day actually free, since people keep trying contact her or book stuff with her on that day.