Later in the season it does seem that more will angle down wind then not. I always try keep my down wind side open so I can see at least 200 yards or so. A coyote is a coyote and just when you think you have them figured out they throw you a curve ball.
You asked about down wind from the call? Down wind from the call and down wind from me are the same since I keep my call very close to me especially when hunting on dark nights while in open fields.
There are number of things that will keep coyotes from breaking cover such as call volume, light discipline, stand approach, boundary lines, calling pressure, etc. It may not just be one thing it could be a combination of things.