According to this article by 9to5Google, Google is preparing to launch a new streaming service called "YouTube Remix" that will replace Google Play Music.
I'm considering cancelling my Google Play Music/YouTube Red subscription if this happens. Google Play Music, although not perfect, is a great solution for me, primarily because I like uploading my own music and it comes with YouTube Red. Although I could, I don't use the YouTube Music app because I like to keep my music and videos separate. Knowing Google, YouTube Remix is not going to have any of the things that I like about Google Play Music.
Additionally, the article notes that in an APK teardown of the YouTube app, 9to5Google found references to a "YouTube Plus" subscription tier. To me, this suggests that either YouTube Red and Google Play Music are going to be combined into the "YouTube Plus" service, or it will be an entirely separate tier.
I'm hoping that Google doesn't go through with this. Google Play Music already works fine for plenty of people, and we don't need another app that already does the same thing that we were able to do previously. Google already has a problem with this (See: Every single Google chat platform)