The Free ticket (DBC free ticket voucher) on United can be used for any flight in the domestic 48 United states, Must be booked at least 2 weeks in advance, you do not earn miles, can only be used on United, not any *alliance partners, but the dates can be changed as many times as you want. You can even book leaving from one city and returning to another, as the round trip, I've done it, JFK-LAX LAX-ORD round trip, bec i wanted to stop there for a week, then bought a cheap one way ticket from ORD-LGA, it is alot better then miles and is can be used to any destination with no blackouts.