The Check-In 2,000 Bonus Mile Promotion ended May 31. This promotion was replaced by 1,000 Bonus Miles Promotion when you use nwa.com Check-In. "Customers who have never used nwa.com Check-In will earn 1,000 bonus miles for using the service between June 1 and September 30. This bonus is not valid for customers who have previously used nwa.com Check-In."