multiple, non-indexed endpoints with the same binding

In SAML metadata, if there are TWO endpoints of type md:EndpointType
having the same concrete type (such as SingleSignOnService) and the
same Binding, how does a relying party choose between them?

AFAICT, this is not discussed in the spec, in which case the behavior
is unspecified, but I may be missing something, which is why I ask.

Thanks,
Tom