Kudos to the My Oracle Support blog for taking the time to respond to my to my comment about searching for Metalink 3 SRs throwing an error.
In essence, if you previously used Metalink 3 you must use https://support.oracle.com. If you use https://metalink.oracle.com/ then you’ll hit the problems I did.
ML3 SR’s are not supported on https://metalink.oracle.com/CSP/ui/index.html. This front end is used for support on legacy server technology, middleware including BEA, and EBusinessSuite
Full details here