In a memo date about two weeks ago, Scott Hall mentioned that they expansion in LAX would be delayed. He did not say for how long. The only thing that was stated was that DAL's plans had changed. They are going to have 4 hard lines for now.
On a side note. They are having major teething pains out there. LAX is not good to do a Mexico turn followed by a domestic turn 45 minutes later. Until they can figure out a solution to this it may be sometime before the true expansion starts.