Re: Age of Milk as baby develops...
The composition of breastmilk does seem to change somewhat as the baby grows. But that change in composition is relatively minor, in that the breastmilk produced for a newborn contains all the same nutrients and immune factors that the milk produced for a 1 year-old does, just in somewhat different ratios. Breastmilk expressed for a newborn is fine for an older baby to drink, and preferable to anything you can buy at the supermarket (animal milk, formula, solids).
Milk in the freezer compartment of a refrigerator does not last that long. I think 6 months, max? In a stand-alone deep freeze, it's good for a year. So if you're storing your milk in anything less than a deep freeze, don't expect it to last a full year. You might want to start pulling out your oldest milk and using it up, maybe using one old bag per day. You should also periodically pull a bag and give it a taste test, because some moms develop lipase issues with their stored milk. Lipase is a naturally occuring enzyme that breaks down fat, and it can make stored milk taste rancid, soapy, or metallic. And even if you don't have lipase issues now, it is possible for them to develop over time.
Another thing that often happens to exclusively pumping moms is that they hit a pump slump sometime during the year. If that happens, you're going to want that stored milk! Because, again, it's always going to be preferable to animal milk or formula, even if it was expressed when your baby was a newborn, and now she's 9-10 months old or something like that.
Coolest thing my big girl said recently: "How can you tell the world is moving when you are standing on it?"
Coolest thing my little girl sang recently: "I love dat one-two pupples!"