I am a little confused here. I anchor with my thumb knuckle right at corner of the back side of my jaw, index finger under the cheek bone and the middle finger just back and below tje corner of the mouth and against a tooth. When I shoot fast I tend to pull a quarter inch longer both right and left handed. It is important to not get the feeling of my jaw bone holding the bow, but instead get the feeling of a stretch when I am at anchor to keep from jamming the anchor. With a naturally bent bow arm when shooting straighter gripped longbows, all of the alignments fall right into place. When I shot target form I too put my thumb behind my neck, just cannot even imagine doing that anymore for hunting.