At the D23 Expo in August of 2015, it was announced that Colin Trevorrow (Jurassic World) would be writing and directing the ninth installment of the Skywalker franchise. Just over 2 years later, in September of 2017, Lucasfilm made a surprise announcement that Trevorrow was leaving the project due to creative differences.
“Lucasfilm and Colin Trevorrow have mutually chosen to part ways on Star Wars: Episode IX. Colin has been a wonderful collaborator throughout the development process but we have all come to the conclusion that our visions for the project differ. We wish Colin the best and will be sharing more information about the film soon.” ( https://www.starwars.com/news/a-statement-regarding-star-wars-episode-ix)
Trevorrow himself remained fairly quiet on the subject. But shortly after his departure, Jack Thorne (Harry Potter and the Cursed Child) and Derek Connolly (Jurassic World) were hired to do a comprehensive rewrite of the Episode IX script from Trevorrow. So there was indeed a script, but only studio insiders knew its state and they weren't talking. In January of 2020, writer-producer Robert Meyer Burnett dropped numerous details on a supposedly leaked Trevorrow script during an episode of his Robservations YouTube show. Trevorrow didn't confirm the script or its plot lines were legit at this point, but it set the Geek-o-sphere ablaze anyway. Multiple sources would go on to confirm his claims and catalog various plot points form the script.
Not too long after the script leak, another leak emerged from a different source - this time in the form of supposed concept art for Trevorrow's script. A fan tweeted to Trevorrow with some of the artwork and asked him to verify it. At long last, he broke his silence. The concept art is legit, the script is at least mostly accurate and the title of his film was going to be Duel of the Fates.
Now that you're all filled on the backstory, you should go check out the leaked concept art and associated plot details. And if you're interested in the Geek's takes on Trevorrow's script, we've released a special podcast episode where John and Eric discuss all of these elements in more detail.