I read the manga prior to watching both the anime and the movie so I already knew what was gonna happen, many others who were manga readers expressed their disappointment with this film especially with the pacing and lack of depth(?) which I didn't really see a problem with. But re-reading the AkiHaru arc, they really did cut out quite a bit of content. Quite a lot of UenoMafu content, as well as the preparation of the concert, and also the depth behind Haruki's feelings and Ugetsu and Akihiko's relationship. The movie was fine, but definitely read the manga for more!