querying the /Status endpoint

[Tom Scavo]

I'm writing a script that distinguishes between IdP V2 and IdP V3 by
querying the /Status endpoint. I've looked at literally 100s of
HTTP-Redirect SingleSignOnService endpoints and they all seem to fall
in three buckets. Each HTTP-Redirect endpoint location ends with one
of the following three paths:

1) /SAML2/Redirect/SSO
2) /Shibboleth/Redirect/SSO
3) /Redirect/SSO

The first variant is most common by far (>99%). There are just a few
(literally) of the others.

Is there some explanation for what I'm seeing? Are any other variants
to be expected?

Thanks,

Tom