LAX storyline is a previous attempt/flashback/reboot, all of the above by Nolan

"It only ends once. Everything before that, is just progress." - Jacob

When the smoke clears (no pun intended), we may very well realize this was the single most important clue given to us during the show.

First I need to give credit to Vozzek69, for even getting me to this point that I can piece together my own theory.

Now, here goes. A large group of people believe the game between Jacob and Smokie has been playing out for centuries, not just pressed on Forward, but on Repeat as well. The events of the island repeating, or being recreated in a similar fashion, moving slowly but surely to a specific "goal". What is this goal? Who wants this goal? Jacob? Smokie? Both? That's anyone's guess.

Think of what brought on Jacob's quote. The Black Rock coming towards the island in the distance. With Smokie saying "It always ends the same." Or basically "We've been there, done this before."

Imagine the LOST timeline as starting from X (and unknown starting point) and going till Y (an unknown ending point).

Every time the current story hits point Y, without fulfilling the proper criteria, we are rebooted to point X again. And each time we replay these loops, Jacob (and maybe Smokie) make subtle influences, to change the next outcome.

Who knows how many times the story played out till we got to Season 1, all the major players finally boarding flight 815 from Australia?

To illustrate my point, let's use Charlie as an example. Let's take a number at random and use that for "the island’s" X attempt.

Attempt 485: Charlie dies after Drive Shaft concert
Attempt 486: Charlie dies in bathroom on 815
Attempt 487: Charlie is saved in bathroom (LAX storyline)
Attempt 488: Charlie dies after being hanged in the jungle
Attempt 489-491: Charlie dies in various manners (lightening, drowning, spike through neck)
Attempt 492: Charlie turns off radio jamming/makes contact with Penny/ then drowns

This is just a small glimpse at one person. During all these attempts, many other small (or large) events also happened to many people and places. But the point is, Charlie needed to live long enough to get to that point, to ignite the next set of events.

Now this is really important, and might be hard to grasp. Many people would quickly assume "the incident" is point Y, or at least an later energy burst (like the failsafe key turn). But I propose that point Y has yet to be seen. And we may never see it, only hear about it. It has nothing to do with jughead, or the incident, at all. Jughead, the incident, etc... have all already happened before (or started to happen) at some point in previous loops. Need proof? Think about the paradox of Ben in the current timeline. If the island was destroyed/moved/sank, he wouldn't still be in the current time. Also, think about Chang's prosthetic hand in the videos. We see him injure it at the Swan site. Think about the Adam and Eve skeletons, who many think are Rose and Bernard. To be that way in 2007, they must be safe and sound still in 1977. Trippy aint it? This has already happened.

These events have all been just smoke and mirrors to distract us from the most important thing that happened in last season’s finale. Smokie "killing" Jacob.

Think back again to their talk on the beach. Smokie mentions how badly he wants to kill Jacob, and how someday he will find a loophole. This means (if you accept my theory), that hundreds of attempts before, Smokie has not been able to kill Jacob. Now he finally has, and this is what will lead us to the series finale and possible passing over point Y for the first time. It only ends once.

What I believe we are seeing, in the LAX storyline, is just one of the previous attempts of "the island". Shannon is not on the flight this time around, did anyone actually see Claire ON THAT specific flight, and of course the biggest surprise was Desmond (who is a whole other debacle of his own). This may sound like a lame twist when dissected. But the concept that this has been happening over and over, is pretty epic when you step back and really look at it.

So that's my theory. I’m sure it has a ton of flaws I didn't think of, and many will dismiss it, and it doesn't answer all the questions, but with LOST, does it ever?