highly unlikely that your loop is moving around , over time your body forgets about your form and thats why practicing consistantly helps you , as you shoot more you get back into your regular form and causes you to move stuff around . only way to fix this is practice more
. I once had a target bow that I shot winter league with , I would leave it in my truck all day and then go shoot after work , until the bow warmed up to room temp it would shoot about 2.5" low and this would happen every time the bow sat in 50 deg or less .