ABBA’s first album for 40 years, Voyage, is set to top the charts around the world in a glorious final act for the Scandinavian superstars. But singer Anni-Frid Lyngstad says “don’t be too sure” that the music won’t still go on. In what sounds like a classic ABBA hook from the 1980s, she told the BBC: “I have learned to say never to say never.” Lyngstad, now officially styled Princess Anni-Frid, dowager countess of Plauen as the widow of a Swedish prince, said that getting back into the studio with bandmate Agnetha Fältskog was like “coming back home again, having fun with my little sister... Once we closed the door behind us in the studio, we felt at home, both of us.” Benny Andersson, Lyngstad’s bandmate and former husband, has said he considers the album to be ABBA’s “swansong”—but added: “There are four of us. If they twist my arm, I might change my mind.” The album outsold the rest of the U.K. Top 40 combined on its release last week, guaranteeing it the No. 1 spot.