Sorry to be a pain, but my memory is playing up. I might be conflating other stuff with Ars Magica.
Basically my confused memory suggests that there are werewolf tribes, basically the untrained/UnGifted descendants of Bjornaer's original infernal tradition, who retain some Shapeshifting virtues. Sometimes attend witches Sabbath on Bald Mountain. Some territory overlap with the Benandatti.
Is any of that in canon? Or have I used other sources?