Frequent-Flier Miles: Best Airlines for Cashing In - WSJ.com: "Cashing in miles has been a source of long-standing frustration. Some fliers set clocks to request free tickets at midnight 331 days, or about 11 months, before departure—traditionally the moment airlines open a flight for booking—only to find no seats available on popular flights. And airlines have raised the price of award tickets by introducing higher-cost award tiers, reducing availability at the lowest award level."
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