A federal program that supports flights across dozens of rural communities in Alaska may be halted as soon as Sunday due to the government shutdown. Subsidies to support the Essential Air Service program are set to soon expire, as early as Sunday, U.S. Transportation Secretary Sean P. Duffy said at a news conference Monday. There are 65 communities in Alaska that rely on this program, across roughly 15 airlines, making the state the “number-one user” of the air service.