The code 1T+xx is (if I remember correctly) old code of KuFlGr 506 (from June 1942), then became III/KG 26 and operated (still with same Ju 88 A-4īs) in Norway/Finland (September 1942), then moved to Mediterranean in autumn (October/November 1942). A/c still with old code but I belive by May 1943 only code 1H+ was used (but I do not remember exactly).
http://www.ww2.dk/air/kampf/kg26.htm