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La leche league had a similar program of donated milk back in the 70s. There was also soy milk as a substitute. My kid's problem was his liver had not developed enough to break down sugars and had to wait a couple of weeks to adapt to the ex's milk. We had a milk machine and turned over the product. The breast evidently adapts to the activity so there is some mutual interaction between baby and mother. It was pretty interesting biology to watch this relationship develop.
You are looking into deep evolutionary development and its interdependence on a social system where multiple women are lactating and babies are a kind of group endeavor. Real anthropology to do that probably hasn't been done.
In retrospect, I can imagine an older baby nursing the ex to develop her tits, and my kid, working on a better developed mother where nursing was easier, a simple older, younger sister or friend---a working women's culture within a larger society. This isn't a men's world. But it was great to watch and study. Well, with psyche support etc. Have I mentioned the smell of a lactating tit? It is an amazing and mysterious perfume, that must have done something to my hormones. We definitely don't understand these social-chemical relationships
Well, and babies produce this or something very similar to this smell. There are many other aspects to this strange relationship. For example, my kid liked to stick his face in my armpit. Only my cat liked to do this, before him. Image that. That's some pretty organic stuff. He tried to nurse my tits, very weird. The nose, the mouth, these are chemical message systems that we never notice, yet they are still at our psychic foundations.