Have Digital Preferred TV service, yet I cannot watch Turner Classic Movies (Channel 169). When I key in the channel number, the screen reads "This channel is not authorized. (V58)." I can't get any help from the xfinity website -- the bot chat is useless, even switching to a human, he gave up andf yet every time I ask for my channel line up there it is, both SD and HD. The chats have asked me to do resets (refreshes) and that doesn't do anything except annoy my household for 4 or 5 minutes!
If you have had Preferred for awhile, you have 'grandfathered' Preferred. When Comcast dropped many of the Encore channels, Epix and Screenpix were added as replacements. If you make any video changes, you could lose your grandfathering and lose Epix, but probably still get Spreenpix.