How much BM is your baby eating

My baby only takes BM I either nurse him or give him a bottle. He is going to be 8 months and he has been eating less he has now gone to 4oz bottles every 2.5-3 hrs. He only takes about four bottles during the day. I also give him oatmeal in the mornings with BM and lunch and dinner solids about 3oz of solid per feeding. I've also sometimes cut down solids to see if he takes more milk but he just pushes the bottle out. He also sleeps the whole night. I feel like he is not getting enough. He is pooping and peeing normal. What about your little ones? Any insights ? TIA