He is definitely ready for a nap at under 3hrs in the morning, he goes down quick. But I have wondered if he could hold out for longer. He does better at night and less likely to have early waking if he has two naps totally not more than 2hrs 45. So we do like the morning nap to be around an hour 15.
If we have longer awake times I fear that the last nap will be pushed so late that bedtime would need to shift. But I guess we could cap that nap to make sure he is awake by 4.