if you are going to cut out anything, cut out the food
if your son was ecxlusively breastfed, you could not see if he was taking 4 oz or 10 oz at a feed! he would stay on the breast until he was satisfied.
with a bottle fed baby, if they are draining a bottle and looking for more, they are hungry and need more milk!!
30 oz is not too much for an almost 6 month old
if you offer milk and allow him to drink until satisfied and he has some food, he will gradually increase the amount of solid food and reduce, naturally, his milk intake, although toddlers still do require milk and / or calcium rich foods
re babies being overweight...if htey are are fed responsively, with milk being the main source of nutrition, it is really hard to make a baby fat!
i personally would give a baby, up to around 12months, as much milk as they wanted with food as a compliment, and not bother too much about exactly a pint or not!
your CM , unless she has read extensively on infant feeding and nutrition is not the best person to take advice re feeding.