Re: How much BM should my 4 month old be eating ?
If the 4 ounce bottles are working, then stick with it. It's likely that she doesn't seem satisfied after the smaller bottles because she still wants to suck, not because she is actually hungry. That is why it is important that your DCP uses paced feeding with the bottle. My son took a pacifier at daycare too, which helped meet his sucking needs. Of course some babies won't take pacifiers and then some mamas don't like pacifiers, which is perfectly fine - just make sure your DCP is trying to soothe your baby in ways other than simply giving her a bottle.
Breastmilk changes in composition as your baby grows to meet her specific needs at each age. Thus, you do not need to give bigger bottles as she gets bigger. My son took 3 ounce bottles until he was well over a year, and he was rolls upon rolls upon rolls fat (he gained a pound a week for a few months in there).
K. Sophia - Mama to my little lactivore, the amazing Mr. X (11/10).