I feel like I'm like most people when shopping for a flight. I go to a website that compares prices for my trip and I make a choice based on some combination of lowest price, best times, and preferred airline.
If it's true that the vast majority of coach class tickets are sold this way, is it likely that for a given flight, tickets are sold in order of the cheapest available fare code first? Therefore, from the perspective of one's chance at a complementary upgrade, at the time anyone buys their ticket, they are probably getting one that has the highest-priority fare code yet sold for that flight?
I'm asking because I recently bought a ticket only a few days ahead of the departure date. It was expensive, but still had a relatively low-priority fare code (I expected a much higher-priority fare code). If the above assumptions are true, this should still be one of the highest fare codes yet sold for this flight, correct?