STRIKE WITCHES OPERATION VICTORY ARROW

The OVA stands for Operation Victory Arrow, and this operation is set in the period between the end of Operation Mars in the second television series and the 2012 Strike Witches movie. The three 30-minute short stories depict the lives of the members who returned to their respective homes. To commemorate this new Strike Witches project, there will be special event screenings of the shorts in theaters. (Source: Anime News Network) — Description from AniList community (anilist.co).