On the day Grant Morrison's final issue as writer of Action Comics is hitting the stands at comic shops, his successor, Andy Diggle, announced via Twitter he's leaving the book for "professional reasons." The news comes prior to next month's release of Diggle and artist Tony Daniel's collaboration on Action Comics #19. It's unknown whether Diggle is still the credited writer on the first issue of the would-have-been run, or if he'll be the credited writer on any of the issues solicited with his name on them through issue #21. According to DC, artist Daniel will be taking over writing duties for the remainder of the arc, although the specific issue number hasn't been specified yet.