I have to be honest, my answer would be 'Any'.
I would need more info to nail it down to a year.
Fair enough - when someone starts banding around Allies in a headline about acts of war etc. if it wasn't for a connection to recent events my mind would go to the most significant use of it in modern history - I don't think there is anything particularly unusual about that. With that in the back of my mind it is a bit eerie to see Allies used in a military context with the UK and Germany in the same camp. This isn't in any way a confusion with our status over the last few decades.
Not even sure why I'm explaining myself here really as there is nothing exactly outrageous about that but it seems to be the theme of today on these forums.