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