I have had terrible sleepers, and my youngest ds used to wake at 4/4.30 am. It's horrible. Those early mornings were soul destroying! No matter if I went to bed early, I would still feel dreadful waking at 4 am.

Honestly, I have no real advice. I tried everything. Really I did, breast feeding back to sleep (which like you, raaarely worked). Refusing to get up until a more appropriate time (usually just ended in tears from one or both of us, as well as waking everyone else in the house), shorter/no day sleeps (ended up with one grumpy little monkey), going to bed later (just meant less time for myself in the evenings), spraying the room/pillow with lavender and other essential oils to induce sleep/relaxation.... I have tried it all.

The ONLY thing that worked was putting him to bed earlier, so at least he got more sleep. I changed it slowly- 5-10 mins every 3-4 or so days, until he was going to bed at between 6.30- 7pm. Even once day light savings started, I insisted on bed time then. And I made sure I was in bed by absolutely no later than 10 pm, which was pretty unnatural for me, being a night owl. I was religious with his bed time routine and time he went to bed.

Now he's 3 1/2 and still wakes early, at about 5.30 am, but that is do-able. *Some* people are up and going to work then, right??? But all of my children are early birds and they are never up any later than 6.30 am anyway. No matter what. The other night they went to bed at 10.30 pm. 3 hours later than their usual bed time. They were all still awake at 6 am. They just all had a nap that day (thank goodness!).

Could there be something irritating/waking her in some way? Her tummy/diet, an allergy, her clothes, hot/cold in bed, noises outside like neighbors going to work.....

I know it's tough and it totally sucks, but she might just be an early riser. I would be trying to get her to have more sleep though. I think 10 hours a day is not really enough for such a littlie (though trust me, I know it's not so simple as just insisting they sleep more!).