I think Rush probably deliberated this issue for quite some time. There is a good chance he might have decided to let the show fade away. It sounds like the plan is to replay some of his broadcasts for the next ninety days, which could be a good-bye OR, possibly a replacement has a contract with another entity that has to expire.
I'm curious what happens to Rush 24/7. You can sign up for a full year.
I think Rush 24x7 can be the enduring legacy to Rush. I was a subscriber many years ago, and can't remember how many back shows they kept. But it would be quite a feat if they could put several of his shows on Rush 24x7. Listeners would hear Rush's thought on issues, many of which are still relevant today.