Megan Mullins

There doesn't appear to be a well-documented, notable band or artist by the name "Megan Mullins" with a verifiable public biography (breakthrough albums, chart history, tours, etc.). Search results show a few different unrelated people with similar names (a Nashville-area fiddle/vocalist performer, a drummer, and unrelated musicians named Mullins), but none match the profile of a band with a documented "formation, breakthrough, career arc, and legacy" as described in your request.