How do I get in a routine when baby wakes at a different time each morning?

[BananaHammocks]

I'm very lucky that my 6 month old sleeps through the night but I'm starting back at work in a few weeks and wont get home til 5.30pm. I aim to have her in bed by 7pm but sometimes can't keep her up past 6pm as she wakes up anything between 4.30am and 7.30am.

Do most babies eventually wake at a similar time each morning?

I'm worried about fitting in cooking, eating, bath, bottle, book, bed if she's falling asleep half an hour after getting home!

Going back to work forced us into a routine really but DS was at a nursery. He'd fall asleep in the pram on the way home then wake up at 6ish, we'd have some dinner, a bit of a play and then bedtime routine and bed for around 8ish

He's older now so doesn't fall asleep on the way home but the routine is mostly the same.