Drawing Date not updating during 'save as'

Currently, our titleblock template includes \\\$PRP:"DrawnDate" in the Date field and this appeared to be working as intended.  However, we noticed that when we perform a 'save as' on a part/assembly and its corresponding drawing in order to create a similar, but different part/assembly, the Date field maintains the date of the originating part.  We need the date field to update to the creation date of the new drawing/model.  Any suggestions?

SolidworksDrawings And Detailing