Ground targeting instant option isn't instant
The other two options work on mouse up. e.g. the skill is cast where you released the button for the skill. The “instant” option now puts the skill where you mouse is after the completion of the skill animation.
This severely handicaps your movement and skill usage if you use this option. The difference used to be it worked on key down for the skill so it was a little faster than the fast option which worked on key up.
To clarify, it looks like skill retargeting is causing this. It doesn’t do this to the other two ground targeting options.