Proficiency is part of the experience package. It would be a shame to waste a shot at a regional by showing up to learn a new turbojet type with little recent flight time. Recency and proficiency are two very different subjects. Proficiency can also be described as a pilot comfortably and professionally completing a mission.
Everyone is different, but simply passing an IPC is not the same as being ready for a turbojet, unless you’ve already been there and done that in a turbine...