Since patch 3 (both on PC and on Mac) I started experiencing a wierd bug.
When I recruit Astarion from my camp and get back to the location I was in, Astarion is always on "a different floor" than the other characters.
It's happened on Rosymorn Monastery where the party was inside the Morninglord chaper whilst Astarion was found on the balcony above, and at the Last Light Inn where the party was inside and Astarion on the roof.