Well if on the day in question he woke up at 8am, and went for a nap at 12.30, then his A was only 4.5 hours, which is on the short side for this age. I think, yes, you might want to push nap a shade later and see if that helps him. Some LOs like a long AM and shorter PM, and others the other way around. You need work out which is best for you. You'll know pretty quickly by BT behaviour! They definitely need more and more A time as they get older, eventually of course there's no nap at all!