>31: The Idol Precure's Center!?
>32: Puri! Mero! Our Dream School Life
>33: Dosko~i! An Idol Debut!?
>34: The Great Detective Hamorin! Pursue the Mysterious Menu!
I forgot we already got most of the September titles. I suppose this all but confirms that Idol's recolor will appear in the next episode.

https://japanese.stackexchange.com/questions/99178/what-does-%E3%81%9E%E3%81%AA-mean-here
Also, I'm not familiar with Japanese novelists. I thought the ぞな might have been a reference to Edogawa Ranpo, but it's apparently a reference to Souseki? Too lazy to look into this further.