Originally Posted by
DownUnderFlyer
Or you interrupt your journey at LAX and book a separate LAX-LHR-LAX to get you home and then to resume the DONE4 at a later stage.
That would also be my suggestion. Your DONE4 allows up to 6 NA segments, and you'll have a year to complete them. Might be just what you need to achieve next status level, or at least a lotta miles to use for upgrades or free travel.
Happy Travel!