Depends on the rut and what your goals are. If your are targeting a herd bull and are in the prime of the rut, the herd bulls will be down with their cows. If it is pre-rut, the satellites might be down herding the cows while the herd bulls stay up higher. Oftentimes, the herd bulls will let the whipper snappers do the herd gathering during pre-rut. Then once cows start into estrus, the herd bulls will drop down and run the satellites off. Of course thermals should dictate your approach and that changes from morning to night.
Going off of the information you gave us, I'd probably start high, but more information would be helpful.