Milk savers - how to store milk?

FTM here - I’m planning on using milk savers to collect leaking milk from the other breast while nursing/pumping. I’ve read that on average, you collect 2oz every time. Any advice on how to store the milk I collect while nursing? Is it ok to freeze the milk, and then add the next two ounces to the same frozen bag? Or do I need to freeze each collection separately to not mix the collection dates? Not sure what I would do with only two ounces of frozen milk? Thanks in advance!