How do our detachment combos actually work?

With 11th having the DP combos that we’re all excited about, do we know how they stack the bonuses/scoring? And then are my units locked to the bonuses of just one detachment at a time?

If I take two detachments with different force dispositions do I score both ways? Pick one?

Let’s say I take CotP and Frenzied Host. If I advance and charge infractors, do they get +2 strength because of the two detachment bonuses? Or is my myriad of questions a mystery until a later date?