Converting my iTunes-matched library to Apple Music equivalents

Thanks for this response, Jim. I should have mentioned, I am already a subscriber to both Apple Music and to iTunes match. As I mentioned, when the match subscription expires, I already have all of my matched library backed up, so I'm all good there.

Your second paragraph begins to answer my question, (again, thank you,) however you don't explain how -- what is the process for replacing a matched AAC file, (or ideally, a whole album - or all matched songs in my library) with an Apple Music version of the same file/album?

In my original post, I pointed out that I already know I can manually delete a matched album and replace it manually with an Apple Music version of the same album. And, yes, I am aware that the Apple Music version will contain DRM. That's fine. But for the reasons I discussed, this is not at all an ideal process to do manually for over 500 albums, with songs distributed across over 25 playlists.

Thanks again, Jim. I didn't share this detail in my original post, but I have been using two separate iTunes libraries, one for my matched CDs, and the other, for streaming Apple Music. However, in the streaming only version, all of the songs that originated in my matched library, are subtly different from the Apple Music streaming versions, which is why I wanted to explore how I might swap them for the Apple Music versions. It appears there is no way of doing that short of spending many many hours manually, exchanging albums and updating playlists.