If for some reason we do not get volunteers then we have to assign it mandatory to whomever has been the longest since they worked volunteered for a holiday.
(In case more than one person wants to work the day, we also give it to the person who has been the longest since working a holiday.)
Last worked (volunteered) Holiday(MLK):
Casey 1st shift
Lori 2nd Shift
Collin 3rd shift
...