I know this is an old thread so not expecting too much from it! My great-grandfather served in 1013 Docks Operating Company aswell from 10/10/42 until 22/9/43 when he was transferred to 1057 Port Operating Company. Did you manage to continue your research into 1013 Docks Operating Company? I have posted some photos of my great-grandfather from his time during the war whilst he was with either 1013 D.O.C or 1057 P.O.C with what I assume is other members of these companies.
Have recently added Royal Engineers units post VE day to my website https://britisharmyingermany.com/royal-engineers