I think you need to keep the 20 yard target, and get another one for 35 yards. That way, you'll get experience with different distances and different elevations. They say that you should experience no difference at different elevations so long as you maintain the magic T, which is the angle between your torso and bow arms. You maintain this T by bending and tilting at the waist. For me, there still are some differences, and I definitely need practice at different elevations, particularly shooting down. If nothing else, it definitely affects my mind, and I have to get used to seeing things a little differently.