to the wonderful world of EBN..you will find all your answers here.
He does seem a little young to already be on adult food Lucy was 8 months before made the switch, and I'm pretty sure she stayed on 3 cups a day until around 5 1.2 to 6 months then I put her on 2 cups but the quantity didnt increase.
I cant give advise on food as I am located in the UK but I shall shout for @desertskybulldogs I know she will help you. There is a very good article here too about the star ratings of food that you will probably find very useful. I'll go find it and post you the link.
BTW we love pics and I for one look forward to saying hello to Winston