User blog comment:B214/Don't ask about season 4/@comment-141.135.80.110-20161022132505/@comment-9595671-20161022181814

It may not be a reboot per say, we do have to remember that Born was apparently caused due to what Loki did in EX, so if we get Volume 5 and 6 again it'd be more of the real universe's Season 3.

Though I have a good feeling it'll be Season 4, people probably want to see Kunou, Yasaka and the Hero faction members we've never physically seen in even art form appear.

Plus, I think people also want to see the Rias vs Sairaorg game, Sairaorg's peerage, the other Trianna forms and CCQ and most of all... see Issei finally get together with Rias.

Also, I recall in Season 1 they fit 5 episodes per volume and used two to show other events. So if it continues from Born, they might just be able to fit an episode for the Rias vs Sona game and the Satan Rangers. (I really wanna see anime Falbium outside of his brief cameo in Born)