Certain servers (like Nginx) can be configured to serve both ECDSA and RSA certificates simultaneously.
Currently, there is no way in cert to control which certificate to test for, and also there is no indication which certificates is actually being tested.
The -cipher(-c) option was implemented. It can specify cipher suite what will used in client hello.(For a list of cipher suites that can be specified, see here.)
As a result, multiple certificates can be confirmed individually.
Certain servers (like Nginx) can be configured to serve both ECDSA and RSA certificates simultaneously.
Currently, there is no way in cert to control which certificate to test for, and also there is no indication which certificates is actually being tested.