As a mum of an early waker I am jealous!
I wouldn't be too eager to get him up at 6. I would set a sort of latest start time of 7.30 or something like that and wake him if he's not up before then. I only say this in case he is trying to shift his day and night round. Just give him a rough structure of when the day starts.
In the meantime, make the most of it!