Forum adverts like this one are shown to any user who is not logged in. Join us by filling out a tiny 3 field form and you will get your own, free, dakka user account which gives a good range of benefits to you: No adverts like this in the forums anymore. Times and dates in your local timezone. Full tracking of what you have read so you can skip to your first unread post, easily see what has changed since you last logged in, and easily see what is new at a glance. Email notifications for threads you want to watch closely. Being a part of the oldest wargaming community on the net. If you are already a member then feel free to login now.

Some Sister of Battle models (Dialogus, Hospitaller) have the "Non-militant Order" special rule:

If your army is Battle-forged, then for each Detachment that includes either a Canoness or Canoness Superior unit, one Hospitaller unit can be included in that Detachment without taking up a Battlefield Role slot.

Is this "freebie" optional? That is to say, if I'm building a brigade detachment led by a Canoness and have 3 mandatory Elite slots to fill, can I choose to have my Hospitaller take up one of them?

.

Yes, you can. It’s a “can” not “must”.