6 month old and solids

My son is 6 months old and has been on cereal and fruits/veggies for about a month now. My question is how do you know when to go to the next step with increasing solids/less bottles, etc?

This is his currently schedule (keep in mind that he is 23 lbs! and has been over 21 lbs since his 4 month checkup)

6am - BF
8 am - 3 tbsp oatmeal and 1/3-1/2 jar fruit/veggie
10 am - bottle
2 pm - bottle
4 pm - bottle
7 pm - 3 tbsp rice and 1/3-1/2 jar fruit/veggie
830pm bottle

When he was EBF he was taking 6 - 6oz bottles a day! Now his bottles vary anywhere from 5-7oz and this is where my question comes in. How do I know when to make his bottles smaller or add more solids? Should he be on a 3rd solid meal at 6 months?

This is roughly my daughter's schedule (she is 8 months but has been on this for about the past month)

Wake up 7:30am- 6-7 ounce bottle
9:30 am- 2 tbls. oatmeal with jar stage 1 fruit
nap 10-11:30
12:30pm-6-7 ounce bottle
1:30pm-Stage 2 jar of fruit or veggie
nap sometime in between here
5pm-6-7 ounce bottle
6:30pm-2 tbls rice with jar of veggie or now that i've started meats-some type of chicken dinner
8:30pm-7 ounce bottle
bed

Nick's schedule is similar to DaniRNs - he is 7 months, and this has been his schedule for the past month:

6:30-7 wake up, 1 jar of Stage 2 fruit and 2 TBSP oatmeal or barley.

7:30 - 6 oz. bottle.

NAP 9 - 10

11:00 - 7 oz. bottle

1:00 - 1 jar of stage 2 veggie.

Nap 1:30 - 2:30

3:00 - 6 oz bottle

sometimes a little nap at about 5

6:00 - 1 jar of state 2 veggie (or meat/veggie mix) and 1 jar of statge 2 fruit or dessert.

7:30 - 5 oz bottle

8:00 bed