Is Sotsu Uta coming back?

Sotsu Uta is a 4-part mini-series based on the theme Graduation. Each episode is titled after a song, which also happens to the song being dedicated (by the female protagonist of that episode) in the fictional in-show radio program Musical Diary. The host of Musical Diary (Nagasawa Masami) appears in the first three episodes as the narrator, and her story is presented in the final episode.