The company's original music service now has an official end of life date: December of 2020.
Not to worry though, the company is keeping pricing the same, and you can seamlessly and relatively painlessly switch from Google Play Music to YouTube Music. This includes having your playlists, all of your recommendations, liked and disliked songs copied over so your preferences will remain intact. Any saved stations associated with your account and of course, all of your uploads and purchases will copy over as well.
Although you may not realize it, the transition has already begun. If you have a Google Play Music account, you now also have a YouTube Music account. All you have to do to move the relevant bits of your old Play Music account over is log into YouTube Music and select the "Transfer" button. If you happen not to see a transfer button, you can navigate to that window simply by adding "/transfer" to the end of your YouTube Music URL.
Once the page loads, you'll see everything that is to be moved across, and all you have to do is click the button to begin. Depending on the size of your playlists, the number of preferences, and saved stations and such, the process could take up to several hours. For most people, it will probably be wrapped up much more quickly than that.
Then, if you prefer, just keep on using Google Play Music until it expires, or go ahead and make the switch now.
In anticipation of Google Play Music's impending retirement, by the end of this month (August 2020) you will no longer be able to purchase or pre-order music using the old Google Play Music site. So if you plan on doing that, you'll probably want to make the switch early to retain full functionality. It's not so much saying goodbye to an old friend, as it is saying hello to an improved one.