Due to the mess caused by Guardians of the Galaxy franchise director James Gunn's firing and re-hiring by Disney over the past two years, it's going to be quite awhile before Guardians of the Galaxy, Vol. 3 sees the light of day. However, fans can rest assured that the film is still slowly but surely being worked on even though pre-production is yet to ramp up.
While answering fan questions on Twitter, Gunn revealed a few tidbits of information in regards to the film's script, including who has seen it and how it's coming along:
WHAT THIS MEANS
It looks like even though Gunn just recently wrapped filming for The Suicide Squad , he's slowly getting ready for production of Guardians of the Galaxy, Vol. 3 . The fact that several people have already read the script isn't surprising seeing as Gunn revealed he had completed the first draft back in 2018, before the firing and re-hiring controversy even began. While he didn't list everyone who's read it by name, it could be noteworthy that he directly mentioned Karen Gillan. While this could just be due to Gillan openly discussing the script (as Gunn mentioned in his tweet), her having already read it could indicate her character, Nebula, will be a major player in the film.
The slight changes mentioned in the tweet aren't anything unexpected either, seeing as most scripts undergo re-writes after the first draft. However, given that Gunn also said that "one other Marvel director" has read the screenplay and that Vin Diesel recently confirmed at least some of the Guardians will be appearing in Thor: Love and Thunder , its very possible that these alterations could be related to that movie (with Love and Thunder director Taika Waititi possibly being the unnamed director). Given that we saw Thor leave Earth with the Guardians at the end of Avengers: Endgame , it only make sense to show the result of that in the next film of either franchise to come out. Had Guardians 3 kept its initial 2020 release date, it would have been the first of the two to come out, but now that Marvel has revealed its slate through 2021 is set to feature Love and Thunder but no Guardians movie in sight, switching that story element to the fourth Thor movie would seem like the most logical thing to do.