Perfect GF baby until now (11.5months old) waking at 5.30am and refusing to go back to sleep, pls help

[C2]

Brilliant contented GF baby until 5 days ago, waking at 5.30am, chatting until 6 then crying. The longest I have left him has been 30 mins then get him up for a breast feed which he is happy with, then breakfast. Had some recent changes, started back at work in the past fortnight, part time, moved house in the past fortnight but he has been fine until 5 days ago. There is no noise from neighbours, we shut his window so the wind wouldn't flap his blind, his room is just about in complete darkness (although some light does get in through the sides and bottom of the window), we live in Western Australia (so it is summer here and the sun is up at 5.30am), he sleeps in a sleeping bag with no dummy or other sleep pacifier, he eats a lot during the day and has 2 breastfeeds (am and pm). Should I try making his room completely dark or just letting him cry for the hour until 7am, I don't know. Please help me...

C2 - from my experience with a successful GF baby, - I would alter the system slightly. You don't say how old he is, but my guess is you need to reintroduce a small milk drink at your bedtime, as many babies during growth spurts can't quite make it through to 7am. I have done this off and on with all mine up to the age of 2 or so, with no ill effects. It doesn't encourage waking as long as you give it in complete silence and near darkness. When they no longer want it they simply refuse it.

C2, not sure if this is relevant as I don't know how old your baby is but have you pushed the morning nap later - to start at 9.30 ish, then the lunch time nap to start at 12.30 ish as he's got older? GF says this prevents early waking but I'm not exactly sure why.

Thanks for your responses. R is 11.5 months old and last night, i put a vest on him under his gro suit and he slept until 6.20am then i thought he had drifted off again but the phone rang about a minute later (can you believe it) and he woke up, but he was chirpy until 6.45am when i got him up. It has been slightly cooler here at night so i am hoping that maybe that was it. He doesn't have a morning nap and has 2 to 3 hours sleep at lunch time. I was considering making this only 2.5 hours at the most but he is always ready to go to sleep at 7pm, drops off straight away with no bother. I guess I'll see how he is tonight.