Alaska Airlines and Delta Air Lines are ending a long-standing codeshare and frequent-flyer agreement, effective May 1. The move also brings changes to the Alaska Airlines loyalty program. All currently booked award travel on Delta will be honored, but changes will not be allowed starting May 1.

Alaska’s upgrades to its Mileage Plan include requiring fewer miles to book flights, more miles earned when flying with select Alaska Global Partners and elite members being eligible for complimentary upgrades on award travel on Alaska-operated flights. The change means members need only 5,000 miles to start booking travel, down from 7,500 miles.

With the Alaska-Virgin America merger now complete, Mileage Plan members can now earn miles on Virgin America flights. Members can also earn up to 80 percent more miles when flying business or first class with select global partners that include carriers like British Airways, Emirates, Icelandair, Korean Airlines, LATAM Airlines and Qantas.

“While many other airlines are heading in a different direction and simply looking at how much people spend, we’re focused on rewarding people across the board for how much they fly,” said Andrew Harrison, executive vice president and chief commercial officer, Alaska Airlines, in a statement. “Our combination with Virgin America, our portfolio of global partners and these enhancements to our award-winning Mileage Plan demonstrate our commitment to creating the most generous loyalty program for our customers.”