Program guide for OTA channels says "loading"

I’m running into a frustrating issue where the program guide for live OTA TV channels says “Loading.” The Plex channels (non-OTA) have guide data. If I sit and wait, nothing changes, but if I scroll ahead in time, sometimes the guide will appear, but the times might be wrong (like it might list a 9 PM show under 6 PM, for example).

Server Version#: 1.43.3.10828.
Player Version#: 10.30.9.4262 (067590ff)
Tuner Make/Model: ATSC 3.0 HDHomeRun FLEX 4K (HDFX-4K).
Guide/Lineup name: Default guide for 29455 zip code
Using XMLTV?: no
Channel number/Name: chan 2.1 WCSC (or any OTA channel)
<If providing server logs please do NOT turn on verbose logging, only debug logging should be enabled>

Fair warning, I’m not neutral here - I run epgwise.com - but since the default lineup is what’s stalling, one option is to bypass it with an XMLTV source. You add the XMLTV URL to the tuner in Plex, refresh the guide, and if any channel still shows blank you can assign it by hand or use auto-map. Wrong start times like your 9 PM show under 6 PM are usually a timezone offset in the source data, which is worth checking whichever provider you land on. To be clear it’s guide listings only, nothing to do with streams.