As it turns out, what looked like Lieut. in writing I can only describe as a stylised scrawl, turned out to be Temp., after using Picture Manager to enhance the image, and comparing the writing to other examples by the same officer, with the assistance of two ex-military colleagues.
supplementary question - two of my Anzacs were promoted to "Acting Corporal (E.D.P.)". What does the E.D.P. stand for?
Cheers
Nudge