How to "undo" a subdivide in edit mode that doesn't show up in object mode?

I was working on some elf-ears in 2.78c, and upgrade to 2.79. The ears had subdivision done on them (from the toolbar, not a modifier) only on some selected polygons - the unselected polygons are where the ears attach to the head, and they need to stay unmodified so the connecting vertexes and UV all match up.

But something is not right in the file now after upgrading.

When in object mode (with wireframe turned on), I correctly see the subdivided polygons, and the ears match the head.
but if I go into edit mode, then it’s as if the subdivision is applied to ALL the polygons (even though non are selected), and of course this pulls the ears away from the head and messes up the UV.

So I’m at a loss - Object mode, it all looks right. But I need to modify the ears, and going into edit mode, it’s all messed up so I can’t edit it anymore.

UMA_Blender_Separated_ElfEars.blend (8.4 MB)

You have hidden the additional geometry by pressing H

Press ALT+H to unhide

Haha! Thanks! I definitely overthought that! Much appreciated.