Re: holy.cow. (literally!?!? LOL) And a milk storage question (quantity)
Our son is on donor milk and while we are grateful for ANY milk we get I do prefer when its packed as much as possible just because when your baby is ONLY taking expressed milk you go through a TON of those plastic bags. And I certainly don't mind the cost, but the waste makes me kind of sad. Seeing all those bags just thrown away (I wish there was a way to make reuseable milk storage bags but I know it wouldn't be as sterile).
We've had donors who pack the bags with the milk from tiny pumping sessions (like one ounce at a time) and we go through a TON of bags that way.
I would ask the mama you're pumping for how many ounces she wants per bag. I know when my son was new we liked 3oz per bag, then as he got older it went up. Nowadays, 6 oz is perfect. We did have one donor mama who packed the bags FULL like 10+ oz each and SURPRISINGLY the full bags didn't leak near as much as the un-full bags seem to which I know the milk bag companies tell you not to pack the bags so full but whatever, it seemed to work.
Kudos to you for donating! Its a wonderful thing to do and I know our family really appreciates mamas like you!