My three hour play session began at the Cocoon of the Empyrean Site of Grace, which is where you do battle with the optional boss Mohg: The Lord of Blood. But this time, instead of an empty boss room, there was an NPC named Leda there as well, who asked me if I too was beckoned by Miquella.
Source: N4G PC Elden Ring: Shadow of the Erdtree First Impressions of the Big DLC IGN