On another tangent on the theme of Time, if one overlays the pivot points of the series time lines around the Flight 815 trip, this comes into focus:
One thing you notice immediately is that the sideways time line starts at two different points on the main island story time line. The sideways beginning point is the 2004 safe landing at LAX, but in the island time line the arrival is 7 days before the island time line ends in 2007, more than three years later in that relative time frame. Since island time memories were the key to the characters revelations in the sideways world, one can conclude that the sideways time line is not chronological.
Now, when the island time lines reunified, the island events lasted another 14 days; while concurrently the sideways time events lasted only 7 days. But even those characters, like Locke, who died before the time merger, retained their memories in the sideways world which apparently was "created" by the island time lines merging after the Incident.
What fed the strong personal memories that created the sideways holding station? One could assume that it is the time riff itself that caused strong emotional bonds to be severed (and thus strongly remembered) until they could meet again. This philosophical approach parallels the ancient Egyptian burial ritual where the soul and body are separated then reunited in the after life. So the concept of Time was not really actual time in the show's construction, by a emotional capsule to capture the strong character bonds in order for them to good friends to help them move on in the after life. Perhaps there is an alternative time for a collective soul to acquire enough life force energy in order to make it to the next level of existence.