In our guild we have discussed this:
It seem that if you are Premium then the Scouting Post gives no bonus at all, we are quite a few experiencing this, is that on purpose ?
That you can have only one bonus at a time? Because then either Scouting Post is completely useless for Premium users
But then again, some who have Premium tell that it works with some adventures, but not with others, i.e. Woodcutters