Hey Jon, I bet you already solved your problem, but I wanted to leave my recommendation in case some one with the same issue finds this post.

Most moss treatments contain a herbicide that prevents seed germination, so I would recommended to wait until your seeds have fully germinated around 6 weeks before applying any moss treatment.

Also late to the party but moss can be easily removed just by raking well. You do not need to apply moss-out..........or any other type of moss killer. Just some elbow grease :-)

btw, most moss-out products for homeowners, like Lilly Miller, are just an iron product - ferrous sulphate monohydrate. No herbicides :-)