Waking out of habit?

My daughter is 18 weeks old and has previously for the past few weeks slept 7-7. She used to wake up in the night and settle herself back to sleep, so we would let her fuss a little before she dropped off again.



For the past week or so she's woken at 5:30 and made a fuss then started crying, so I've offered her food and she's downed 7oz. She's now consistently woken at 5:30 and done the same for the past week; due to it being at 5:30 every day is it likely that she's doing it out of habit or just because she's hungry? I assume because she's hungry because she has so much milk.



She still goes back to sleep afterwards for another 1-2 hours, and it doesn't bother me too much, I just want to see whether people think it's something that she might stop again!



Tried giving her extra milk last night and she took a total of 12oz in the hour before bed and still woke at 5:30. She'd usually have 8oz before bed.



She's a big girly and 18lb+ at 18 weeks so it wouldn't surprise me if she just needs more food. xxx