WW1 Tank Corps Officer Cadet?

[Shiny]

Hi All,

I've just been sent these photos of a Great Great Uncle, I know he got a commission into the Tank Corps right at the end of WW1, around October 1918 and served until at least October 1919.

Would I be right in thinking the white band around his hat means this was taken while he was an officer cadet?

I know this is the wrong forum but has anyone any idea what the ribbon would be? He was in the 1st Northumberland Volunteer Artillery and 1st Northumberland Brigade RFA(T) between 1900 and 1910 and when he joined up in WW1 he wasn't mobilised until 1917 if that helps.

Thanks a lot,

Michael