Not necessarily. Every airline does things differently. Unless there is an introductory fare though airlines will usually price out far in advance an average fare for what they think the route is worth. As it gets closer in, they will usually adjust the price for demand and have sales if they want to fill more seats. They will also make adjustments based on the competitions' fares. Once you get more than 3 weeks away then fares start to rachet up as the plane fills and you pay for the convenience of the short notice. Fares will also get higher sooner for high travel periods and holidays. I find usually the best prices are 2-3 months out depending on when you plan to fly. Since like you said its not a busy flying period when you are going you should be able to get some decent fares.