Goats rut in November +/- a week. There will always be some pre rut posturing stuff, just like you see with deer/elk, but that doesn't mean they are actively breeding.
There may be a billy or two in a nanny group in September, but they will typically be a younger billy 1-4 years old. Bachelor groups of billies will usually be found within a few miles of nanny/nursery herds. It is pretty common to see pairs of billies, where one of the billies is quite a bit older than the other.
As for "where," goats will be where goats will be. Billies, nannies, and kids will all be in any of the same places at the same or different times. But they generally don't have a massive "home range" most of the year. That changes when billies go into true full rutting behavior, when they will just start cruising miles and miles everyday, rarely staying still.