Animation retargeting adversely affects looping animations

Retargeting a skeleton to a looping animation results in the animation skipping at the end of the loop (Appears to miss 1 or 2 frames.)

Open UE4.6 CL2357962
Create a new project using third person blueprint template
Import Animation Starter Pack
Retarget the default character skeleton to any looping animation
Note at the end of the loop, the animation appears to skip