In LA X we were introduced to two parallel time lines where in the first:flight 815 never crashes,they land in LA,and live happily ever after.
and in the second:They return to 2007 and there's some Jacob-MiB things going on.
Many people ultimately figured that Jughead created two unconnected timelines.
but I think that Jughead Cannot change the future at all(See prooflink
Then My theory is that after Detonating Jughead it prevented 815 from crashing,thus preventing the survivors from detonating it in the first place,creating the other Timeline.
and,both timelines will continue repeating over and over again,until someone does anything about it.
Thanks for Reading!