I am trying to find a way to group a production report by a run of a product. We are constantly changing the products we make on a machine, so a part can be being made for a week, then another one for the next week, then back to the previous part for another week. I need something along the lines of "If date1 is > 3 days difference from date 2, then group"

I don't even know if this is possible, I really can't think of a way to accomplish it.