Looks to me like he was now a Fitter IIE (Aero-engines), this may have been his original technical trade before he volunteered to aircrew; this was known as "reversion" to basic trade. Other somewhat connected trades were Fitter IIA (Airframes), and Fitter I (cross trained and qualified as competent on both airframes AND aero engines). (The term "Fitter" generally indicated that the subject had passed through the earlier "introductory" stage of the process - these earlier trades being Flight Mechanic, and Flight Rigger respectively, although prewar there were other trades such as carpenter (airframe) and another equivalent for metal aircraft, something like "Rigger (Metal)" - somebody with a better knowledge of RAF pre-war tradesmen might like to correct me at this point!
David D
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