Delta announced today that for flights on or after 6/1/16, "the number of miles needed will change based on destination, demand and other dynamics." The dynamic award pricing that was foreshadowed by the removal of published award charts has finally arrived.
Delta also expanded the fare classes for which mileage upgrades can be redeemed, but simultaneously increased the price between 2-3x on average. For example, US-Europe upgrades could previously be obtained for 25k SkyMiles. Now they are 60k, or 80k if redeeming from the newly eligible lower fares.
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