United Mileage Plus members who reside in Illinois or California can earn double elite qualifying miles (EQMs) and double award miles on flights between Chicago (ORD) and Los Angeles (LAX) or San Francisco (SFO) through Aug. 31, 2011. The double mile offer is valid on United or Continental nonstop, roundtrip flights that do not include additional or connecting cities on the itinerary. Registration prior to travel is required at http://www.united.com/offer/mpd771 – Only flights purchased and flown between May 19 and Aug. 31, 2011 are eligible to earn double miles and previously booked tickets do not qualify. There is no limit to the number of bonus miles you can earn through this promotion.