The movie Private Benjamin was released in theaters on October 10, 1980. The TV version premiered on April 6, 1981, the first of four episodes before returning with a full season in the fall. Was any other movie turned into a sitcom in less than six months?

If you include shows which were based on or adapted from movies, Delta House (adapted from Animal House) was a little faster at 174 days vs. 187 days for Private Benjamin.

Gung Ho (266 days) and Nothing in Common (246 days) also had fast turnarounds.

I used this handy online calculator to determine the amount of days.

https://planetcalc.com/274/

List of television programs based on films

https://en.wikipedia.org/wiki/List_of_television_programs_based_on_films

Live action television shows based on films

https://en.wikipedia.org/wiki/Category:Live_action_television_shows_based_on_films