Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from Krabi to Sydney as you normally would.
Related info for your journey
Useful info, stats and facts about Krabi to Sydney flights.
These are just IATA (International Air Transport Association) codes. They are used in aviation to identify and differentiate airports. That’s why a Krabi Airport to Sydney Kingsford Smith Airport flight would often be abbreviated as a KBV to SYD flight.