They could have just stopped maintaining it. Versions that were already released would still be open. Nothing you can feasibly do about that. But if they no longer wanted future versions to be open source, they could have just announced that, and offered consulting services to add features, fix bugs, etc. Albeit, there'd be no way of stopping someone else with a fork of the last MIT licensed version from continuing open source development.
They could have just stopped maintaining it. Versions that were already released would still be open. Nothing you can feasibly do about that. But if they no longer wanted future versions to be open source, they could have just announced that, and offered consulting services to add features, fix bugs, etc. Albeit, there'd be no way of stopping someone else with a fork of the last MIT licensed version from continuing open source development.
Completely agree here. Not much else you can do if older versions of your software are OSS, free of charge.