Hi Sapper,
War Diary of 2nd Bn attached. 2/Lt Handley was wounded on 14/04/1918, in the front line near Ayette.
I suggest you upload the free Bn War Diary sections from the National Archives site. There may be earlier references to him, probably noting when he arrived for duty.
It's interesting to think of the connection between your grandfather and his peer, Wilfred Owen. It would be worth checking Owen's records because he certainly mentioned other officers in his documents.
Welcome to the forum.
Tim