Marvel is on the cusp of ending this major phase in the Marvel Cinematic Universe, with the first half of Avengers: Infinity War coming this May and the second part in 2019. Until now, no movie past Infinity War has been scheduled aside from the next Spider-Man film, but James Gunn has confirmed that 2020 will be the year for the next Guardians of the Galaxy movie.
The news comes from director James Gunn's twitter, which replied to a fan question about when the third movie would be arriving. Gunn replied "Coming in 2020."
Gunn confirmed he would be directing the third Marvel movie about space-faring heroes last April. A little while later in a Facebook Q&A, Gunn hinted that the third movie might incorporate Nova into the story. "Nova comes up occasionally as someone we might use," Gunn said. "We're going to be setting up new characters. It's going to really expand the cosmic universe [and] will be the last movie of this version of Guardians of the Galaxy."
The Guardians are also in Avengers: Infinity Wars, which you find the trailer for below.