One thing I wonder about is the quantity of new copies they pressed for the reissue in October of 2015 (for the individual steelbooks and the repackaged complete saga).

Would they have made all the copies they thought they were going to need for the following two years all at once or do they make them in more limited batches and only make more when the supply runs low?

I’m probably reading too much into the “every two years a reissue” pattern, which could simply be coincidence. The 2015 reissue was definitely timed to take advantage of the coming onslaught of new movies. I can’t help but wonder why they wouldn’t continue to milk those same discs until after Episode IX is out and Star Wars mania starts to die down a little, and only then think about releasing the original versions.