I had posted somewhere once before that I beleive the scene of K/J airport was part of the end of season 4 which I still think so. And I think that Jack is trying to convince Kate they need to go back to the island as I think Hurley might do with Sun, think the flash forward of when S/H at Jin grave might be the lead into him telling her they all need to go back to the island.
Jack has said he's tried getting back to the island on his own and he can't so I think the only way any of them can get back is that all have to be together in order to do so. I just can't figure in how Sayid going to be part of this cause he's running around doing deeds for Ben. Then maybe again the reason Sayid hanging with Ben is cause he's the one that can get them back to the island. Can't be too hard to get Aaron to go back since he's with Kate. That's my input about timelines sorry if I had confuse some I'm just throwing this out there.

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Standing in the ocean with the sun burning low in the west
Like a fire in the cavernous darkness at the heart of the beast
With my beliefs and possessions, stopped at the frontier in my chest
At the edge of my country, my back to the sea, looking east