My understanding view is that the first aircraft gets most of the waiting passengers (for equal fares). The next gets what's left, the numbers increasing to an average level over an hour or so, more if there are big aircraft involved.
I am not sure how Sami has actually programmed this, I would assume a low level of departing passengers over night, increasing and prepared to pay more, as the morning progresses. From my own experiences of getting cheaper flights that usually means flying at unsocial hours, and queuing for everything, but that's Ryan Air's model.
FlyBe out of Southampton rarely has queues for it's internal flights, opening at 6am for first flights at 7? and pax numbers being pretty constant through out their working day.