It will center on the fifth part
During a JoJo bizarre adventure event held in Osaka it has beenr evealed that a new anime based on the 5th part is in the works and it will premiere on this fall.
While no key visual or teaser has been revealed, the staff has been revealed as follows:
Tsuta Tsuda is serving as the General director while Yasuhiro Kimura and Hideya Takahashi are the directors of the anime at Studio David; Yasuko Kobayashi is in charge of series composition; Takahiro Kishida is in charge of the character design.
Via: JoJo´s Bizarre adventure anime webpage (Japanese)