My sympathies, DS is 2.5 and has been doing the same thing for a few mornings, if it was every day I'd be going mad! This morning was a 5:30, yet yesterday was 8:15 - couldn't believe that!
With DS these things tend to go in 3/4 week cycles tho, just as I get used to early wakings, he starts sleeping longer. Sadly the reverse is also true tho...
What time does he go to bed?
We know that someone young on our road must leave for paper round/school at 6:30 as for a big chunk of the summer holidays DS woke at 7:30-8ish, then the week the schools went back he started waking at 6:30 on the dot every day! This has settled down since, I guess he's finally got used to whatever noise he hears.
I find DS always wakes sooner if its cold in his room, as he always kicks his blankets off earlier in the night, so he's stone cold by early morning and often wakes early then comes into my bed for cuddles and rubs his little iceblock feet all over me. We've got a tower heater on thermostat in his room, but sadly can't put him in grobags anymore as he's in a high big bed and would struggle to get in/out in them.
DH leaves for work around 6, so goes in quietly to put DSs blankets & duvet back on, this has really helped him stay asleep longer.
We're thinking about getting one of those moon/sun clocks that are supposed to teach them when it's time to get up - various kinds but I think the Gro Clock is meant to be good, the moon glows blue as a nightlight when they're meant to stay in their room, then the sun glows yellow when they can get up/downstairs.
Hope some of that is helpful!
Have now seen the time, bloody hell, DS'd better not be up at 5:30 again tomorrow as its now today - and in only 4 hours! Pregnancy insomnia sucks.