Usually when you drop a bottle, either the other three bottles increase or you make up for the lost ounces with a snack. If your LO will take a sippy with formula, I would replace that bottle with a snack and a sippy of formula. Otherwise just a snack and try and increase the ounces in the other three bottles. I don't know how many ounces your LO is taking now, but once they start to eat more solids, their formula intake will decrease.