I have the same issue. I now sit with a really expensive 4k camera that's stuck in an unwatchable resolution with no PTZ menu to change it back. My 5mp camera is in the same boat. I purchased a UTC Controller but guess what? They only work on 1080p and bellow cameras. This is truly a BAD move from manufacturers.
Why put the setting there if there's no going back?
Why not warn people on the box or manual?