2yo suddenly needing a lot less sleep?

My 2.5yo has been mostly a great sleeper. Always in another room on his own, I keep a strict schedule so for a while now he's been sleeping 730p-730a through the night, and I would have to wake him up at 730 to get ready for daycare. He also would nap at school for about 1 hr. I know 13 hours of sleep seems like a lot but that's what worked for him.Now in the last week not only has he not napped at school (30 min max if anything), he's sleeping 730p to 330 or 430a. I just don't understand how he suddenly doesn't seem to need 4 hours of sleep he was getting before. He's averaging 9 hours a day now. He also wakes and walks into my room, insisting on either laying in my bed or watching a movie at these god awful hours. Is this common, maybe some kind of regression? He's my first and I'm just kinda lost right now. Should I push bedtime back a little so maybe he'll sleep in later?Edit: his activity level hasn't changed either. He runs around all day at daycare/playing outside so that's not the issue I don't think. via /r/Parenting http://ift.tt/2y8Vrgp