Blackout blind made zero difference - what am I missing?

Early waking is the final boss and light is only one piece. For us it was bedtime being too late causing overtiredness, plus the first nap being too early which made the night 'feel' long enough by 5am. We pushed the wake window and it shifted.

Check for light LEAKS, even a thin strip at the edge of the blind can do it at dawn. We taped blackout fabric around the whole frame. But also, sometimes it's just hunger or a too-early bedtime, not light at all.

The 4:50 wake is so often about the body clock thinking the day starts then. We treated everything before 6 as night, no lights, no talking, boring as possible, and over a couple weeks it drifted later.

Is she cold in the early hours? The room temp drops before dawn and that woke ours at almost exactly 5. A warmer tog sack fixed what the blackout blind couldn't.

UPDATE from OP: it was a combination. There was a light leak at the top of the blind AND her bedtime was too late. Fixed both, treated the 5am as night-time, and we're now getting to 6:15. Not perfect but I'll take it!