I seem to remember this bug a Long time ago, so I wonder if it's the same.
I just saw it happen. I've got the file open, and it looks fine. Hit render, it's fine. Send to queue....rendering and one of the parts mapping has changed.
It's not my file. I was just helping a coworker figure out what was going on, so now he's just gotta send them one at a time. But I believe it was set to planar map to a slightly curved surface. He imported the model from solid works. I'm not sure if he sent it as step, or used native.
Sorry folks, that's the best I got. Hope it helps.