Okay sure, but that army doesn't exist and is currently not announced to exist in the foreseeable future.
Honestly I don't really like shared troops. It's less of a thing with Ghulams and Fusiliers and such, but I like each Sectoral to be quite unique (which is fortunate, as a Haqq and Nomads player!)
And yet weirdly, unlike Invincible Army, White Banner apparently has a logo, and the dossiers of Red Veil and Beyond mention White Banner as much as they do IA (And ISS). Also, the Zhanshi are literally called Troops of the Banner.
It was actually kinda annoying in N2, there were a lot of Ariadna profiles that were literally copy/pastes of each other. But one was a Minuteman and one was a Moblot, or one was a Paracommando and one was 6th Airborne (just the ones I can still remember)
It used to be more of a thing when they were samey, yeah. I think they're way better at making those units feel distinct these days.
It was said at the warrior round table at interplanetario, CB posted a blog post with the Q and A some time ago