Walt, LOST in Time?

I’ve been thinking about the introduction of time travel to LOST, and the interaction of the time-skippers with people in the past. I suspect that at some point, Walt will return to the island, but the island has been moved in time and so he will return at a point in the past, and will, among other things, try to warn Shannon to be quiet and tell John Locke to get up, he has work to do. While the island (or the smoke monster) has regularly manifested itself as the dead, Walt is the only still-living person that I can think of who has appeared in places he could not normally have been. Time travel might make sense of this, and if the producers do indeed go back and account for this aspect of the earlier story, it will be yet another example of the brilliance of LOST.

If I were asked to speculate further, I would guess that at some point, Walt will be transported into the past and will get off the island, and will begin working towards some goal involving the island and those with whom he crashed on it. And just as John Locke had to use a different name, Walt too will have to disguise his identity. He’ll call himself Matthew Abaddon.