As far as I can tell this mainly applies to Apple TV client. The ‘On deck’ image is just a black/gray box with no image. This applies to recorded DVR shows.
Additionally naming of groups such as News etc. is not consistent. News is “News” and Sports is “sports”. Just looks daft.
Apart from that I’m not having too much success with HDR and the experimental player but I have to test a bit more to be conclusive.