Sarah Perez, writing at TechCrunch:
With Apple Music Replay, subscribers will get a playlist of their top songs from 2019, plus playlists for every year you’ve subscribed to Apple Music, retroactively. These can be added to your Apple Music Library, so you can stream them at any time, even when offline. Like any playlist, your Apple Music Replay can also be shared with others, allowing you to compare top songs with friends, for example, or post to social media.
Here’s mine for 2019. Looks about right.