User blog comment:B214/Volume 22 spoilers/@comment-95.90.227.74-20161022133329/@comment-9595671-20161023220106

No, they'll be adapting the Kyoto arc and the rating game against Sairaorg. And since Volume 8 only has the one non-side story chapter, I think they'll use an episode for that, and I have a good feeling the other will likely give us the Rias vs Sona game or maybe a different short story.

The First season technically only used 5 episodes for the first two novels, as the Student Council didn't show until the third novel and some of the clients Issei went to in episode six were also from a short story. So I'm pretty sure they can do that again.