Welcome to BYC. Glad you decided to join our flock. It will just be a mixed breed unless you happen to have those rare White Leghorn hens that have the silver factor gene in which case you would get Red Sex Links, but I wouldn't count on it. Most likely the offspring would be primarily white with some red flecking. One rooster can efficiently breed 10-15 hens so I would think most of the hens would have been bred within a few days. Just to be on the safe side, however many chicks you intend to hatch, I would set double that number of eggs. Please feel free to ask any questions you may have. We are here to help in any way we can. Good luck with your hatch.