I am not sure if this is a DVR issue or an Android app issue (leaning towards Android app issue), but the UHD Movies section is not updating as UHD movies are added. I can still see the new movies in the Recently Added section and the 4K tag is present, but they do not show up in the UHD Movies section. The Apple app (TV and phone) both are updating as new 4K movies are added.
Also, I noticed this section is called "UHD Movies" in the Android app, but is called "4K Movies" in the apple apps.