Do you actually know he's been waking up at the time you think he has in the mornings? I thought my DS2 was waking around 6amish until one morning I woke up at 5am to go to the toilet & took a peek into his room & he was awake just looking around etc & I kept checking on him & he never went back to sleep... then spent a few days checking on him & he was doing that every day. So where I thought he was sleeping 7.30-6am, with a nap it was actually 7.30- 4.45ish with a nap, but he was happily in his room that hour or so. So it could have been he was awake at sometimes in the night /early morning & you didn't know about it, but now has stopped & that's why he doesn't need the nap. When DS2 dropped his nap he used to do one day/week where he slept from 4.30-7am, where as a normal night was more like 7pm- 6.30am.
