I run into the same issue as @talking small, but had the Artist.latestRelease property work before. I think since the update to 15.4 it returns nil.
Just my two cents if this might be helpful.
Henlin70
Users receive reputation points by contributing quality content to the forums.
Posts include post and replies published on the forums.
Post authors can mark replies as Accepted to indicate successful solutions.
Apple Developer Forums admins can mark replies as Apple Recommended to indicate an approved solution