Fun fact: if you call ticketmaster customer service, if you push hard enough, they WILL exchange your tickets for different, still available tickets, for a fee of $7 per tickets.
What I've heard from various sources is that they're gonna do European Arenas in winter/spring 2016, South American Stadiums in summer 2016 and, finally, North American Stadiums in summer/fall 2016. (Oceania in 2017)