There's something in the works that might help with rapidly changing m3u's:
So you could have something like IF 'title' contains 'Baseball' THEN set field 'tvg_logo' to 'http://www.image.yea/baseball.gif' AND set Parent to 'Make Parent'.
Couple this with the automation routines Playlist Manager: Update Station List, Playlist Manager: Update m3u(s) & XML EPG(s), and Refresh Channels DVR m3u Playlists and you could conceivably push things like this from original source to Channels as often as once an hour.
What about combining m3u-editor along with StreamLink manager.
The software can sync as often as you like plus you can push known feeds to Playlist manager and assign icons.
When i have a live event that changes often, i will put the ain URL for the service i'm using in Playlist manager and when the event is about to play for the day, i will update my stations and find the link i want and specify linking to live event 1 or live event 2 etc.
when i look for URLS for events, i try to stick with static links that alwasy play what i want.
Depends on the setup and provider.