Upvote:2
Usually the cheap airlines adapt their pricing to demand, so basically they are trying to set the price as high as possible while selling all the tickets at the same time. So it is usually not possible (or very hard at least) to guess when the prices will go up or down.
In general they tend to be higher during peak times (school holidays, events, bank holidays, etc.). From my own (limited) experience during these times the tickets are more expensive even when released and the price rarely falls.