I've found early archery bugling activity to be highly variable year-to-year. Case in point, my 2016 hunt began on the Friday of opening week (Sep 2), and I bugled in and killed a satellite bull that evening. The very next morning, I bugled in a larger bull for my brother. Both bulls had been bugling before I began calling to them. In 2018 I hiked into the same canyon on opening day (Aug 25), heard maybe a half dozen bugles all week, and killed a cow late in the week.