Delta Air Lines said its frequent fliers can now book one-way flights starting at 10,000 miles.

The new lower starting rate for one-way flights booked at least 21 days in advance on some U.S., Mexican and Caribbean routes is one of several changes Delta says it is making to improve the program. Atlanta-based Delta’s previous starting rate for one-way flights was 12,500 miles.

Delta has been seeking to make changes to its frequent flier program amid complaints about difficulty in using miles for free flights. The airline also said Monday it will allow frequent fliers to redeem their miles with more of its airline partners, and will allow elite-level members to earn elite status through flights on most of its airline partners.

The changes come after Delta transformed its program this year with frequent fliers earning miles based on dollars spent, rather than distance flown — part of its focus on rewarding high-spending customers such as corporate travelers. Last month, Delta removed from its website the charts that show customers the rates. Instead, frequent fliers can view an award calendar while searching for flights in the booking engine.