Hi Karen, yes 6 months would be ok, as my hens hatched in the first week of July (so are coming up for four months now), and I am now putting them into their own accommodation. I also have an older batch of hens that could have the cockerel for a few weeks, so he doesn't tread the young ones too early.
It would be better if I came across, as I don't know when the lunch finishes, so if you could pm me your postcode I can find directions easily (have all the OS maps of Scotland!).