How to reproduce

 - Set up a contraption where a piston pushes or pulls another piston (such as a piston extender - See images)

 - Power the piston being moved as soon as it becomes solid again

What was expected

 ** The piston model would update as soon as the piston being moved reaches its destination and is powered

What was observed

 ** The piston model remains the same for a few ticks after being moved, but the piston head itself is duplicated