Grease: Rise Of The Pink Ladies is a great prequel to the classic movie musical Grease, but the show accidentally creates a huge plot hole in Grease. Set about four years prior to 1978’s Grease, Rise Of The Pink Ladies shows the origins of one of Grease’s main greaser groups, the Pink Ladies. Following a completely new cast of characters, Rise Of The Ladies both succeeds at further developing the world of Grease while also updating the movie’s universe and music for a modern audience.

https://screenrant.com/rise-pink-ladies-grease-timeline-rydell-plot-hole/