If they are going to already start filming in May, JJ must already have selected the principles for the film? I'm surprised that hard choices haven't leaked.
Even with Trek we knew many of the main characters that close to production time.
Not so surprising. Back when it was just Lucas making these things they managed to keep a very tight lid on them, now with Disney in the mix...well, let's just say I doubt there are many people in the business stupid enough to violate an NDA with the Mouse House.