Shadows from objects slightly offscreen

I have an object that casts a nice looking shadow on terrain. But as I "truck" the camera laterally and the object slowly goes out of the scene, its shadow disappears in a really unnatural way. This problem appears on IOS but not in the Unity "Game" window in the editor. It's not easy to describe or even show the problem in static images, but the issue appears to be that as the object goes even slightly offscreen, it stops casting shadows that would appear onscreen. The shadow ends abruptly and unnaturally at a particular line along the terrain. I've increased the "bounds:extents" on the object's skinned mesh renderer to no avail.