Due to multiple factors, expect to potentially pay more when booking in November. For low rates, March can be a great choice for travel to Flint. Flights to Flint from Missoula in March are about $389 on average during March, but can be found for as low as $244.
Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from Missoula to Flint as you normally would.