Well, at the moment, I think Montero and Jaso are going to be the catchers until Zunino is ready, which may not be for two years. In the meantime, they might use someone like Moore (assuming he stays) or another veteran like Olivo to help fill time.
There's also always the possibility that Zunino never makes the major leagues. The team has to be ready for that possibility and not put all it's eggs in a single basket (which might also explain why they drafted a ton of catchers last year and a high profile catcher this year).