I doubt the sculpt was intentionally changed at all. Many of the times, when casting from resin to PVC, using a steel mold, you'll get shrinkage vertically across the head, it's hard to explain, but when you see it, you get it. You see it when the cheeks shrink inward. That's likely what happened here. The unfortunate part about it, is that it's almost impossible to control, because that's just nature of things, they expand and shrink according to temperature, so when you the items when they're poured are under intense heat, and they cool into the harder finished items, they'll warp. That's just what happens, it's science.