> Kodak monopolized the aftermarket for parts and service after their customers were "locked in."

It's not clear to me that the timing was essential. Apparently Kodak had a policy since 1975 to only sell parts to direct purchasers of equipment, but the initial case wasn't filed until 1988. So the official terms, which were between Kodak and customers, not Kodak and ISOs, hadn't changed recently.

Clearly Kodak was taking some non-official anticompetitive actions, but that's not the same as changing the official terms.