Good day Jennifer (jennifera),
At present I don't know of any plans to add the ability to enter vacation / holiday time in advance of that time. I am tagging the Orthotrac Product Line Manager uriyahrobinson to make sure he is aware of this suggestion.
Thank you for your interest in this feature!
Phil Carter / Orthotrac Escalations
It would be nice to be able to do it on the same day or ahead of time because quite honestly it's just a pain to remember after a long weekend and inevitably someones time card gets screwed up every couple of months.