JQuery draggable objects reverting to the wrong location

I'm using JQuery draggable objects for a custom exercise. Distractor objects have revert set to "true" & correct objects have revert set to "invalid". I've discovered that when the object is rotated on the screen, the revert always returns the object to a negative x position. Screen grabs are provided below.

Has anyone here encoutered this before & found a solution? It's a minor problem but I would love to fix it! I have attached a simplified version (L19) here.

Thanks in advance. :)