Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from Dubuque to Fort Hood as you normally would.
For a flight from Dubuque to Fort Hood, you will be flying from Dubuque. Dubuque (DBQ) is just 7.1 mi from the center of the city. Dubuque is the only Dubuque airport and it handles 0 outbound flights to Fort Hood per day. 0 airlines have flights to Fort Hood from Dubuque on a regular basis.
These are just IATA (International Air Transport Association) codes. They are used in aviation to identify and differentiate airports. That’s why a Dubuque Airport to Austin Bergstrom Airport flight would often be abbreviated as a DBQ to AUS flight. Killeen Fort Hood Regional Airport (GRK), Waco Airport (ACT), College Station Easterwood Field Airport (CLL) are other airports near this flight route and their unique identifiers/IATA codes.