There is disclosed a method for a user equipment (UE) in a wireless communication system, receiving pending network slice selection assistance information (NSSAI) including one or more single NSSAIs (S-NSSAIs), and applying the received pending NSSAI to at least one second public land mobile network (PLMN) in a registration area, wherein the UE is assigned to the registration area comprising two or more tracking areas (TAs) including at least a first set of TAs belonging to a first public land mobile network (PLMN) to which the UE is registered.