So yeah RHCP is very likely gonna be a 3 parter, if not 2 parter.
Actually make it 2 parts being RHCP and the 3rd part being about finding Shizuka Joestar.
Following that we have
2 parter for Hirohiko Araki
RATT
Rohan and Koichi's friendship frolicking in a haunted alleyway
Harvest (2 parter?)
David Bowie enters the scene (2 parter)
Cinderella
Sheer Heart Attack (3 parts)
Atom Heart Father would be 1 episode
Course the first of the Stands that Yoshikage Sr. awakens is Rock Paper Scissors kid
so yeah give it 3 months for the most batshit battle in this Part alone.