I am pretty curious as to what is the deal with the survivors of Ajira 316 right now? I mean, sure, they are having a great time. They are on a second island, thus they're not threatened by the monster, but still.
My theory:
Remember back in season 5, we saw the boats on the beach Frank, Sun, and Ilana's group used. What if they join the battle too? Probably on the side of Jacob, since (in my opinion at least) they confused John Locke for the monster. That could be one reason why they were firing on the time travelling survivors.