I anecdotally find flight prices tend to follow a cosine wave. Starting high, dipping a couple months before, and shooting back up. You can see these sorts of trends on Google Flights which will show historical pricing for your search query.
And it can be helpful if you’re very flexible. If my dates are very strict then I’ll tend to book further in advance, whereas if I have a lot of wiggle room then I’ll wait it out.
My biggest takeaway from this article is that I should go and see which of these systems have APIs I can query, because if I have a lot of flexibility I think it'd be easier to script it than clicking through a whole bunch of different options on google flights trying to find what the cheapest fare is. I want to be able to write a script that says "here are my dealbreakers, here are the range of dates I can leave on, here's the range for coming back, go and find the best deal"
I guess that's the type of service people typically build and charge for.
And it can be helpful if you’re very flexible. If my dates are very strict then I’ll tend to book further in advance, whereas if I have a lot of wiggle room then I’ll wait it out.