Apparatuses, systems, and methods for user equipment (UE) devices to perform a radio access technology (RAT) upgrade. A UE may initiate a background scan to upgrade RAT while camped on a first system in response to an occurrence of a first condition. The first system may include a first PLMN that operates according a first RAT. The UE may determine a second system operates according to a second RAT that provides upgraded service as compared to the first RAT. The second system may be included in one or more systems found during the background scan. The UE may attempt to register on the second system based on the second PLMN operating according to the second RAT. The first and second PLMNs may each have an associated operator preference and the first PLMN may be preferred over the second PLMN.