I'm pretty new to this forum, so I'm not sure if rules questions should go in a different place.

For Feathered Armour, what stats does one use? Should I just use the Encumbrance and Protection of a Leather Shirt or Leather Corslet?

Feathered armor seems to be a modifier to any type of armor. I haven't had a player choose this reward yet, so this is a new one to me as well.

AB p.140: "Radagast has blessed these suits of armour with his cunning, and now they don’t seem to make a sound when worn, whether they are made from animal skins or rings of steel". (emphasis mine)

The way I read it, I would rule that when a player chooses this reward, the player chooses ONE specific type of armor and that reward is attached to that ONE armor. Don't let them mix and match. Of course, if they get a reward further down the road and want to upgrade their current armor, I would let them move the FA over.

You know, that makes sense, Kaltharion. Thanks!