Organizers have announced that the Michael Jackson tribute concert scheduled to take place on Sept. 26 in Vienna has been canceled, Reuters reports. Instead, the event will take place in London in June 2010, to mark the first anniversary of Jackson’s death. On Tuesday, Jackson’s brother Jermaine and organizer Georg Kindel said at a news conference in Vienna that the tribute’s roster included Mary J. Blige, Chris Brown, Akon, and Natalie Cole. The very next day, however, they backtracked and cited various conflicts with those stars’ schedules.