Well, I finally got around to watching it, after hearing such glowing reports and have to say that I think the first hour was classic British comedy, especially from Terry-Thomas (absolute shower!), but then felt it tailed off a bit and overall wasn't a patch on its sequel.
Private's Progress (1956)
No ,it's very good though.
Do we know R A's full name in it? I can't remember.He's Sydney DeVere Cox in the second.What else could he be but a crook?
Shown as Private Cox on the IMDb