F.B.
Our DS is the same age. He is in bed at 8pm and wakes at 6:30-7:30 am like yours does, and as late as 8ish on the weekends. He gets a 90 minute nap/ quiet time at daycare 3 days a week. When he is with my parents two days a week, he naps anywhere from 1-3 hours sometimes as late as 2 or 3pm -5 or 6. The same is true during weekends with us. The late naps have never been cause for him to go to bed any later. Hubs explained, and we have found, sleep is cumulative. A late nap, doesn't seem to give cause for any less sleep.
We have only the occassional night waking. Main difference being, ours is still in a crib, so he usually wakes, puts a mobile on or talks to himself and goes back to sleep.
I haven't offered you any tips, but I hope that our experience might help set your expecations.
F. B.