Releases in Avion are a collection of stories that—when shipped together—will deliver working, coherent software for your end-users. Depending on the maturity of your project, this could be an "MVP" or it could be a particular feature set, like "Ratings & Reviews". Some customers use releases for time-based delivery cycles, like Q1 and Q2, for example. However, it's worth noting that releases are not intended to be used as sprints in Avion. The story map is agnostic of your sprints.