DALLAS (AP) -- Southwest Airlines is revamping its frequent-flier program with changes designed to nudge customers into buying higher-priced tickets by letting them earn bonus flights faster.

Southwest says passengers will be able to redeem points for any flight without blackout dates, even international flights on other airlines.

CEO Gary Kelly says the overhaul will bring in "several hundred" millions of dollars in extra annual revenue within three or four years.

Southwest plans to announce the changes Thursday and launch the new program March 1.

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