Though the release of Ballsy! World Cup 2020 was successful, many players reported playing in the daytime gave them a bad case of sunburn. And so, management decided to add random nighttime fixtures to the schedule. Teams can also specifically request to play in the day or night at all times, by setting the relevant 'match time' slider in the match options menu.
The rendering pipeline has been restructured to support for this lighting update; if you bump into graphical issues, please let me know on the discussion boards!