I would say if you know he's eating healthy then don't bother changing anything.

My ds is 90% for height and has been mostly that all along. He was quite chubby on just bm. But as he moved more the weight gain decreased dramatically. I think he was still putting on 300-500g month at 12m. But then at his 18m, after walking/running, he only put on 500g over 6 months making him 50% for weight.

I think after he was 15-16m he was on 2 bf and 2 bottles cows milk a day. Now he's on 2-3 bottles cows milk a day.

In the end you know your child better than they do.