When will my Sumatra Hens start to lay

I recently bought 8 Sumatra chics at a local chicken auctions they are now maybe a few months old, my roosters have just begun to start crowing and showing thier pretty tail feathers.. Can anyone tell me about when the Hens should start to lay eggs? I had 3 roosters and 4 hens but sold my biggest rooster last week leaving me 2 and i lost one when they first came home. I love these chickens they are beautiful and very friendly and would rather eat bread than anything.. They will escape if not contained well however they can fly like no other chicken i have seen before