Don't think its an Australorp.. due to those yellow feet... My Australorps are 13 weeks right now, and only the Cockerels have any waddle or real comb development... the pullets i read don't start to really develop their combs and waddles until a week or so before they're ready to lay...
I recently got 17 BA in May, and they looked just like that. I'd say they're BAs, can you pick one up and see if the under side of its foot is a light pinkish white color?