In the event I don't have enough milk stored, is it possible to formula feed while I'm at work & then breastfeed when we get home? I am going to try & minimize shifts to 4-5 hrs. long but some may be 8 about 3x a week. I know everyone is different but I'm curious to know if I will be able to keep my milk supply. Has anyone done this or have any tips that may help me??