What to do about a Medicare Advantage Plan that's being terminated

Even if @JohnT doesn’t make an appearance here in time, you may find it helpful to read some of their distilled wisdom at:

It’s a huge thread, but there are a couple of summary posts near the start that give you at least the background of what you need to know.

Rules are a bit different when you’re changing plans midstream, so take what is written therein with a grain of salt. Some of what it presents as options may only apply when you’re starting at age 65.

Best of luck to you and your father.