I usually hunt starting Labor Day weekend and we get into bugling bulls so the first week should be ok. The rut kicks in a little later, but I've had good luck calling bulls in close because the cows weren't ready yet. I think you will be fine either week, just be prepared to enjoy the hunt whether or not you kill a bull. The success rate is about 20% for archery which means 80% go home empty handed. There is nothing like hunting in the rockies, so enjoy the experience! Get in shape!!!