As seen in the screenshot below, all the 8.x channels, for example, 8.7 (MOVIES) show up in the HDHomeRun channels list but cannot be selected in the EPG. They do not exist there. I can watch the missing channels through the HDHomeRun app without issue, but, they are simply not available in Plex. 8.7 MOVIES is the most important missing channel for us.
It is the same with both HDHR tuners (Flex 4K and Connect) with the Local Broadcast Listings.