I have added a dozen playlists to my library on Apple Music, which are managed by Apple or other organizations, so they get updated. When I go on road trips, I use Wi-Fi to download all those playlists before I go (because the internet reception out of the city is bad). I am using the Apple Music app on an Android phone (Samsung Galaxy S8).
I have decent storage space on my phone, and Apple Music is currently taking up 11GB. However, I want to be cautious about how much storage space is getting used up. Are the songs I downloaded from these playlists previously, in the previous version of the playlists, still stored on my phone, or are they deleted? If they are on my phone, where are they? I probably wouldn't use the old songs, because my main way of listening to songs is to use these Apple playlists, as well as "radio station creations". So, I would want to remove the old songs if they aren't automatically getting removed.
To clarify: I'm not adding the songs from the playlists to my library. I'm only tapping the download button at the top of the playlist.