Breastmilk storage!

Any of the overproducing moms! I breastfeed and I still have to pump so much because I WAY overproduce and I also work part time so ofcourse I have to pump at work. I have a chest freezer FULL of milk but I feel like I need a better organization system to it. Right now bags are in a gallon bag and I tried to give it a number system, but then the ones that go in first end up at the bottom and the newest ones end up being used first! Its driving me crazy, anyone have an suggestions or something that worked for them??