Supernatural just held its final panel at SDCC in Hall H with J2M, Alexander Calvert, and the executive producers. Rob Benedict and Richard Speight Jr. moderated.
J2M broke while thanking the fans
Season 15 picks up right where the finale left off.
Eileen and Adam are apparently returning, along with Rowena!
Jake Abel is confirmed to return + Matt Cohen is directing an episode - along with Jensen (currently directing 15.04, which started filming on Thursday) and Richard Speight Jr. (directing 3 episodes).
Sources 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12