Waking earlier and earlier

[Crazyone84]

My 4 month old has been a pretty good sleeper at night. Since about 3 months she has been sleeping 8pm till 7.30am. During the day she is a cat napper (5 or 6 naps anything between 20 mins to 45 mins) which I don't mind as she sleeps at night. For the last week or so she has gradually been waking earlier and earlier, 6.45am 6.30am and this morning 5.55am! I'd like to try and get her back to around 7am. Is this sleep regression? Or do I need to start structuring nap times? We don't force naps I let her decide when she sleeps but always take her queues. We tend to be in and out alot so she naps at home on bouncer, on me, in the car or while in pushchair when walking.
This morning I left her to chat to herself and she did drop back off after 20 mins then woke 15 mins later, I left her again and she slept for 10 mins then we got up. TIA

Sounds like a mix of the sleep regression and also the mornings are a lot lighter now could that be waking her? If so could you look at black out blinds or curtains to see if that helps?

I did think maybe the lighter mornings.....we do have blackout blinds but sun hits our bedroom window first thing and light gets in around edges. I may invest in one of those gro anywhere blinds and see if that helps. She does seem like she could sleep for longer just doesn't settle fully. I just don't want her making a habit of 5am!!!!

While in the phase of short, frequent maps as you are, it's easy to move around bedtime. Just by adding in an extra mini nap you could make your bedtime later.

I'd move it significantly later at first, say 9.30pm ish. Give it a couple of weeks at that so that you can reset morning wake up time. But then settle on somewhere around 8.30pm, 8pm at the latest for bedtime.