James Gunn was fired from the movie due to old tweets, only to be rehired by Marvel and Disney months later.
Gunn's momentary exit from Guardians of the Galaxy 3 resulted in a significant delay for the film. He was hired to direct Guardians of the Galaxy franchise.
According to a new report from Guardians of the Galaxy Vol. 2 moved its production to Atlanta. Screen Rant has reached out to James Gunn and Disney for a comment about this development.
It won't be too surprising if Guardians of the Galaxy 3 starts filming this year. Disney and Marvel have yet to give Guardians of the Galaxy Vol. 3 an official release date, but Kevin Feige did confirm a theatrical 2023 release date. It is widely believed that the threequel will receive the same May release window that Guardians of the Galaxy Vol. 2 had. The Marvel machine has previously run at a schedule where production begins roughly a year before the project's release date. If Guardians of the Galaxy 3 starts filming in 2021, Gunn should have some extra time to complete the movie. Additionally, the slightly earlier start could be happening so Gunn can film The Guardians of the Galaxy Holiday Special.
As long as Guardians of the Galaxy 3 stays on track for a 2021 start to production and 2023 release, six years will have ed between installments of the franchise. Not only that, but the events of Guardians of the Galaxy 3 will likely take place a full decade after the Guardians' last team mission. Their next adventure will undoubtedly be different with the alternate universe Gamora off on her own. Still, Gunn has described Guardians of the Galaxy Vol. 3 as the end of the current iteration of the team. He's also said that it sets up 10-20 years of cosmic MCU stories, so there's no telling what Gunn has planned.
Source: Murphy's Multiverse