Rolling Stone is reporting that Green Day in a Los Angeles studio with longtime producer Rob Cavallo working on their follow up to 2000's Warning. The album is expected in either late summer or early fall. Frontman Billie Joe Armstrong commented "We've got about thirty-five songs we're going to record… It's a lot of material. We're trying to get one theme throughout the album, because we're in the album business, not in the business of making singles."