It's a marathon, not a sprint. It doesn't matter if Johnny is on red and Amy is on lilac as (a) different schools go at different paces and (b) children develop different skills in different order.
I can't quite believe the number of reception reading threads I've seen this week along the lines of "what colour book is yours on?". I'm going over to the behaviour/development board now to check for obsessive posting about when children learn to walk. Cos it doesn't matter either, in general.