TUTORIAL: Setting up Catch-up in NextPVR backend

If you use NextPVR to ingest your IPTV streams and feed them to Kodi or Emby, getting Catch-up (Flussonic/Xtream) to work correctly requires some URL manipulation. NextPVR by default just passes the direct channel URL. To enable 3-day catch-up: 1. Open your NextPVR web interface -> Devices -> IPTV Device. 2. In the 'URL Format' override box, you need to use the `{start}` and `{duration}` variables. 3. Xtream Codes format: `http://server.com/live/U/P/{channel_id}.ts` changes to `http://server.com/timeshift/U/P/{duration}/{start}/{channel_id}.ts` for catch-up requests. 4. You will need to write a small python script to rewrite the M3U to intercept these NextPVR requests and format them properly for your provider.