Old Aug 26, 13, 3:57 pm
  #2  
NeverFirst
 
Join Date: Jul 2011
Programs: BAEC Gold, LH M&M Member
Posts: 2,697
Yes. Just hold off putting any FF number in the system until check-in time.

If they join OW before then you will also get any benefits due if you have status (luggage allowance, lounges, etc).

Bear in mind that it's possible that the earning classes may be restricted (you may not earn points on certain booking classes) but I doubt that has been decided yet.
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