When flying from Cebu to Nebraska, the time of day you decide to fly out makes little to no difference towards the overall price you’ll pay on tickets.
These are just IATA (International Air Transport Association) codes. They are used in aviation to identify and differentiate airports. That’s why a Cebu City Mactan Intl Airport to Omaha Eppley Airfield Airport flight would often be abbreviated as a CEB to OMA flight. Lincoln Airport (LNK), Grand Island Airport (GRI), Kearney Airport (EAR), North Platte Lee Bird Field Airport (LBF), Scottsbluff Scotts Bluff County Airport (BFF) are other airports near this flight route and their unique identifiers/IATA codes.