Reason for the change, Jacobs death, not bomb by Crooked

So we know that Elloise knew that Daniel was going to go back in time and she was going to kill him but she let him go to the island anyway, per her telling Widmore she had to sacrifice a lot.

Therefore any and all events that happened during their time travel had already happened in our current timeline that weve been following since season 1.

If that is true and the incident that took place on the island was always the events of "THE INCIDENT"(last seasons finale) then juliet hitting the bomb did not cause the plane not to crash and inevitably land in LA.

Then what did cause the plane to land in LA.

My theory is that it is Jacob's death that caused the Alt Timeline to happen. If we are to believe that he is some type of deity being then we can assume he lives outside of time and his death at anypoint in any timeline could have dramatic effects among all timelines.

This may be a little much but I think there is something to it due to CC and DL recent comments that we may not yet be aware of what changed to cause the plane not to crash.