What was his routine for a morning nap before starting daycare? That would probably give you an idea about his sleep patterns. My babies who start with me usually around 10 months of age drop their morning naps really quickly because they are having so much fun. But if we are travelling they sometimes nap for a short time in the stroller.

When my babies drop their morning naps I feed them lunch at 11 and get them into bed by 12:30. However, if your nap schedule is more like 1-1:30 before you get your group into bed then I'd let him have his morning snooze. It's all depends on your routines. I can be flexible by just nudging the times of things about 10 minutes every couple of days until the children become slowly accustomed to the new way so that all of the children are comfortable.

When I had an older group of all ages 3 & 4 we had the later lunch and later naps, but now that I have babies again we have the earlier lunch and the earlier naps for their sake and the 4 year olds have adjusted. Children can't tell time at this age, so if you do it slowly, their bodies adjust.