...
reading back in time, I posted a pic that shows SR can copyright both, (Performance and Words and Music = SR for everything only if you did it all).
...
Ask a Music Lawyer: Which copyright forms do I use? How many do I need to fill out?
The link article is dated 2011, so is not something I'd read for an up-to-date interpretation!
And, these things change all the time. The copyright office will continue to tweak this stuff and may change it substantially again, but the current rules are pretty clear (as this non-lawyer read the initial public record) - you cannot submit a group registration for songs/music anymore unless they are
unpublished works, and the current limit is 10, which must be individually uploaded, BTW. Whether you use PA or SR, I don't know for sure if it matters in this case, but the Standard Application cannot be used to register a
group of published recordings. (Start an application and read the restrictions if you want to confirm this.) I suspect you could upload your album as a single SR (one file), but you won't be able to list the individual songs - at least that's my expectation.
Or, put another way, if you've got a published work, it must be registered individually, and not as part of a group.
Now, the copyright office has continued to not be specific about what "published" actually means in the age of the internet, so you might be able to fudge your way through this if you're able to clean up traces of anything that they might decide means published, but you really don't want to get into a discussion with any government body about whether they are right or wrong about these things, so I'd try to use the system as it is, until it changes (again). Just my (earned) $.02.
Federal Register link from back in February:
https://www.govinfo.gov/content/pkg/FR-2019-02-13/pdf/2019-02185.pdf
P.S. Given the pace which these applications are processed, you won't be able to search and see what's been registered, and how, for a few months, since this rule took place in March.