to be squeezed into two seasons, fall starting in December and Spring starting in March. Football will end March/April depending on how far you go in the playoffs. Boys basketball season will begin in March and end in May/June.
https://cifss.org/news/july-20-2020-update-and-2020-21-sports-calendars/. Things might change between now and then, but that is the official word for Southern California.