Just to say I brought the Xbox One X version again this evening as I fancied playing it again, and i'm extremely disappointed.
I'm on a Scorpio model btw.
With HDR on I have none of the shadow issues, but with HDR when there is a storm or dark clouds the sky box is dire with banding and artifacting everywhere. This is due to the coloured textures for the sky box in certain conditions not being a high enough resolution (it's similair banding you will see present in cut scenes in certain games where it's pre recorded video and not rendered by the games engine. Shadow of Mordor suffers from this quite badly). I've never played with HDR on as I honestly don't care for it in many games (I'm on a Samsung 65 inch Q7F).
So with HDR on the game can be quite ugly in places, with it off you get the shadow errors making caves etc unplayable.
I've gone back to the digital version on my PS4 Pro, and with HDR off the game is absolutely fine. So in sum i've wasted money on another xbox copy (traded my original copy few months back for another game). When I Last played on xbox it must have been before this "ghost patch" as I had no issues playing 4K non HDR.
I'm now going to trade this into Game.co.uk for cash so I can at least get some money back, and think I'll stick to PS4 Pro version.