Katarina interaction with Grag's E

Sometimes when you shunpo behind him while he E's, it will still knock you up even though it does not collide with you, and is proven, by him still moving forward and completing his animation. You will be behind him, he will keep moving forward, and you will be knocked up no where near his path.

When Grag's E properly hits you, he stops moving forward. So it's really easy to tell if you "mistimed" it, or not.

Please fix this interaction. It's very inconsistent. And quite annoying.