if GTA 6 is next, when will rockstar announce it, seeing as they announce their games 2 years before release generallyGTA V marked the start of all of their studios working on a single game.
Several of the GTA V leads from Rockstar North were also in charge of RDR 2; Imran Sarwar, Phil Humphries, Aaron Garbut, Phil Hooker.
A smaller-scale game like Bully is possible, but I don't know if it would happen before GTA VI.