Baby bedtime?

We are sleep training my four month old so I feel like she's figuring out her bedtime.  The first few nights it was 7:30, then last night 6:30, and tonight 6! She always wakes up around 5:30 no matter what bedtime is.  During the night, she only partially wakes when we feed her then she goes back to sleep.  I definitely think the early bedtime is better! I'm not getting her out of her room until 6 am, which is what I've been doing.  Does anyone else's baby go to bed really early?