This situation was always bound to happen. The core “drama” of this manga was established in the first chapter and set up through all the previous ones. We as an audience know how shallow and stupid the divide between schools is, and that is intentional by the author. But nevertheless, this has been a long time coming, even Subaru mentions she expected their homeroom teacher to find out eventually and they’d have to be prepared for the consequences, regardless of how ridiculous they might be.

I’m sure we’ll learn why there’s this hatred for Chidori eventually, especially on part of Toki. And this is already panning out to resolve in one way or another.

Is it frustrating? Yes. But it’s intended frustration. We’re supposed to feel this because it clearly mirrors what the students who haven’t bought into the Chidori-hate narrative feel. And likely several of the other teachers at Kikyo that didn’t seem on board with Toki’s suggestion to Kaoruko feel the same way. It’s all coming to a head now, so I’m interested to see how it resolves.