Wake to sleep? Help please!

[pinguina]

DD2 is almost six months, FF, and has slept through the night (6.30 to 6.30) since she was 4 months old. BUT! In the last two weeks she has started waking up before 5AM: and I mean completely awake, and shouts from her cot to get some attention. If I try and ignore her, she starts crying. She is not hungry, and will wait until 6.30 to be fed. She will take a bit of water, her dummy etc, and be quiet for maybe ten minutes, but then starts shouting again, until I pick her up and play with her.
As she is waking DD1, I have tried last night to do the 'wake to sleep' technique - I set the alarm for 4AM (shock horror), but was actually awake at 3, in anticipation. I stroked her tummy and when she moved a bit I put her dummy in, and left.... But she still woke up at 5. So now I have been awake since 3 and am shattered!
Shall I try again tonight? Should I wait for another few weeks and see whether it is just a phase?
HELP!

The first few mornings can be hellish.

IIRC you need to almost wake her 3 mornings in a row, you may or may not see a change in waking on these mornings. Then you don't disturb her sleep on the next 3 mornings, she might well wake later. If not then you need to almost wake her again for another 5 mornings before you try not disturbing her sleep again for another 3 mornings.

It's quite a while ago that I last did WTS, so I might not remember it quite right. Try searching in the archives for more advice.

I worked really well for both my DC, they both improved after just one cycle of WTSing.

Thank you!
I'll try again and see if there's any improvement...