Dorico, NotePerformer and libraries with Sections

I am using NotePerformer with NPPE and the CSBrass library. This library, like several others, has solo instruments and section instruments - in this case two trumpets, two trombones, four horns etc.
On the NP page under ‘Mapped Instruments’ it states that the section instruments are also mapped as well as the solo ones…My question is: Under what circumstances to these section samples kick in? For example, I have a French Horn in the NPPE Playback Engine with four staves allocated to it, and and if I look at the Kontakt instance in advanced settings, I can see the patch is ‘solo horn’. If in Dorico I have all four horns playing in unison, I’m guessing that I should be hearing the 4 horn patch, but I don’t think I am. Many of the other libraries have sections mapped, so does anyone know how and when they are triggered? Do you need to use a playing technique maybe?

Okay, well for those interested, if you use CC 104 - That will change the sound to the section sample where CC104 = 0 or 1 = solo, CC104 = 2 = two players, 3 = three players etc. The thing is, if the only section in the library is four players, then CC104 = 2, CC104 = 3 and CC104 = 4, will all play the 4-horn patch (at least to my ears). That’s fine. Now, if you have a single note in horn 1, then in the next bar repeat the same note in horn 1 & 2 (unison on different staves), it somehow seems to trigger the section automatically because it sounds the same as if you were using a CC104 = 4, even though initially in my original post, I thought otherwise. Three horns in unison will also sound the same as 2, which in fact is four horns, because as I’ve noted, in this library, there is no 2-horn section. No problem. So, maybe we don’t have to use CC104 because it seems to happen automatically. I’m just trying to figure out what’s going on under the hood with a2, a3 and a4 sections, and some clarification would be useful, but maybe I just need to leave it up to NP, which seems to do an amazing job on its own. It’s quite a remarkable piece of software.
I’ll share a little anecdote - My wife is a professional cellist and always turned her nose up a little at my string programming/phrasing, which irked me somewhat. However, I played her a little string doodle with NPPE and CSStrings and she immediately said it sounded so much more realistic. This alone has sold me on this system which I am now transitioning to. I think layering NPPE libraries is probably the way to go, but you certainly need a lot of RAM, that’s for sure.

I’ll post more info if I become any the wiser on this topic.