If you have all possible NPCS you can access at the Wayfort Bar - Jael'yn, Rumie, Nina, Sandra/Caera, Talulah and Piperita, Piperita will disappear as an option until Jael'yn goes to sleep at the barracks, which opens a slot. If you check the 414 day save below, before I've recruited Sandre/Caera, Piperita is available 24 hours a day, but on the 423 save she disappears because I've recruited them, only appearing when a slot opens when Jael'yn moves tiles.