We see this on PC (Windows in this case) with Oculus Rift retail hardware (SDK 1.3) - Unreal Engine version 4.11.2
It is a real show stopper for us using instanced stereo rendering (hoping for a hotfix!!!)
[EDIT] Apparently this is fixed in CL 2960162. I’m going to integrate that in our engine to verify if it solves our issues.
[UPDATE] It is fixed when we integrated the mentioned changelist.