Want to remove disk from Time Machine but preserve backups on it
Forgive me if I've missed this in the archives, despite endless hours poring through the discussions. Many of them come "close" but none "quite there."
When I hit the inevitable "Time Machine disk is full" message I added a new drive to TM to backup my MacBook Pro running Mojave. At the time, I selected the option to add the new drive to the rotation instead of replacing the old drive. But now I'd like to have my cake and eat it too – use only the new drive while preserving the backups on the old drive (2 years' worth, many client files w/multiple changes, etc. that *might* be needed some day).
If I remove the old disk, can I still go back in time to retrieve files on it should the need arise? Or is there some other way to accomplish what I'm looking for?
MacBook Pro 15″, macOS 10.14