The core idea is that a release can live in more than one place at once.
When label pages launch, a release uploaded by an artist can be associated with a label's page - so it appears in both the artist's catalog and the label's catalog. This supports real-world scenarios where an artist releases music on a label but also maintains their own presence on the platform.
Artists who join Subvert now don't need to wait for their label to have a page. Their releases can be connected to a label page retroactively when the feature is ready.
This also means that if an artist has released music on multiple labels, each of those releases can be associated with the correct label page while still living on the artist's own page.