Connie, the latest research shows that breastfed babies drink the same amount of milk each day from 4 weeks of age until solids are introduced ( usually 6 months). Then it decreases very slowly. The daily amount will vary from baby to baby but about 750ml per day is average. Formula fed babies would be the same in that their calorie requirements will be static until nearly 12 months of age. Ff babies might need more solids earlier to make up their nutrition but the milk is still most important.
I would say that the type of solids would factor in too. Rice cereal and purees are low calories and therefore shouldn't replace milk. Meat and dairy foods are important early foods and are higher calorie. If milk is being reduced by so much you would need lots of that in his diet I expect.
Did you ask the doc where he got that info from?

