Development on the forthcoming Marvel Cinematic Universe film Guardians of the Galaxy Vol. 3 has officially been put on hold while everything behind the scenes of Avengers: Infinity War is ironed out.
Partially because some of what happens with the Guardians is dependent on what happens with them in Infinity War.
Considering all of that, Guardians of the Galaxy Vol. 3 definitely feels far from becoming a reality at the present moment.
However, in due time things are sure to become more solidified behind the scenes of Avengers: Infinity War, and James Gunn will undoubtedly be allowed a clearer conception of where the MCU is headed post-Phase 3.