Okay so ftm. I have 2 questions first is how long is BM good for in the freezer? Second is I'm only producing 2-3oz per session that I pump. Is okay to add milk to the same bag throughout the day so that I can fill a bag instead of having multiple bags that are not full? If so is it okay to mix fresh milk with milk that's in the fridge or should they be the same temperature when I mix them?