Seeking for advice from those who feed their baby with S26.

I'm currently feeding my 11 month old baby boy with S26 (Step 1). This coming January he will be 1 year old and I tried to survey for S26 (Step 2). To my surprise, i notice on the packaging of Step 2 state the milk is for 6 months old to 12 months old and Step 3 is for 1 year old to 3 year old.

Quite confused on this as the packaging for Step 1 clearly indicate from 0 months to 12 months old. How come Step 2 is from 6 months to 12 months?

Is it okay for me to directly change from Step 1 to Step 3?