I've been there, done that, still sometimes doing it. My ds is almost 13 months. From 8 months to probably 10 months, he was getting up super early...as early as 4:45 am, which in my book, is still the middle of the night. :wink:
He was never a good napper, so if it was a bad nap day, I'd put him to bed early...6 or 6:30pm with the hopes that he'd feel rested enough to sleep longer in the morning. That helped with him being better rested, and sometimes he'd sleep past 5:30am (maybe 6 once in awhile), but it was hit or miss. As he got closer to 10 months and started learning to walk, he was taking better naps because he was so tired and then he started going to bed closer to 7pm. He started sleeping in a little bit more, much better than 4:45, but his internal clock is set at 6am. Rarely as he ever slept later.
I've tried putting him to bed earlier and I've tried putting him to bed later, but I think that is just the way he is wired. It's such a delicate balancing act between not too tired and tired enough. And in the end I just want him to get enough sleep, KWIM?
I'm not sure if any of that is helpful, but I think a lot of babies go through that stage.