A Much Improved Crash Landing
So flight 316 seems to have done a much better job at delivering people to the island than flight 815 did. The plane looks like it managed to land in pretty much one piece with a much better survival rate.
So this is the purpose behind the runway the Others were building for “the aliens”. The emergency landing of flight 316. I wonder who actually told them to build it.
It could have been just Ben looking out for himself. He was on the plane afterall and I guess making sure there’s a runway to land on is a good way of improving the odds that you’ll survive a plane crash. The question is how the heck did he know he’d need one? If this is the case then Ben has quite a bit of knowledge about the future (his future in particular) which wouldn’t actually surprise me that much given his previous behavior and how he always seems to have a plan (like he knows what’s going to happen next).
Maybe it was Jacob. In that case it looks like maybe Ben is supposed to be back on the island. That kind of makes sense to me as well. Based on what Christian told Locke at the bottom of the well it was supposed to have been Locke who moved the island, not Ben. So Ben wasn’t supposed to leave in the first place.
Anyway, mystery solved (I think). The runway was for flight 316.