Skeletons Strafe off of Cliffs

I really like the new AI for Skeletons, but I discovered a bug (I think). I tested this multiple times, where I put a Skeleton on a platform in the middle of a pit, and varied the deepness of the pit. (tried 1 block deep with lava in it, 2 blocks deep with lava in it, 3 blocks deep with lava in it, and 5 blocks deep without lava in it). All of the skeletons fell into the pits while shooting at me in survival. Hope I helped if this is not intentional.