It can be anything! An apex, subdomain, or even a URL.

Results forwebmail.mysitecms.com

Logged At	Not Before	Not After	Common Name	Matching Identities	Issuer Name
2021-09-12T11:46:36.722	2021-09-12T00:00:00	2021-12-11T23:59:59	mysitecms.com	webmail.mysitecms.com	C=US, ST=TX, L=Houston, O="cPanel, Inc.", CN="cPanel, Inc. Certification Authority"
2021-09-12T11:46:36.334	2021-09-12T00:00:00	2021-12-11T23:59:59	mysitecms.com	webmail.mysitecms.com	C=US, ST=TX, L=Houston, O="cPanel, Inc.", CN="cPanel, Inc. Certification Authority"
2021-06-28T06:57:51.511	2021-06-28T00:00:00	2021-09-26T23:59:59	mysitecms.com	webmail.mysitecms.com	C=US, ST=TX, L=Houston, O="cPanel, Inc.", CN="cPanel, Inc. Certification Authority"
2021-06-28T06:57:48.952	2021-06-28T00:00:00	2021-09-26T23:59:59	mysitecms.com	webmail.mysitecms.com	C=US, ST=TX, L=Houston, O="cPanel, Inc.", CN="cPanel, Inc. Certification Authority"
2021-04-13T06:57:22.148	2021-04-13T00:00:00	2021-07-12T23:59:59	mysitecms.com	webmail.mysitecms.com	C=US, ST=TX, L=Houston, O="cPanel, Inc.", CN="cPanel, Inc. Certification Authority"
2021-04-13T06:57:21.707	2021-04-13T00:00:00	2021-07-12T23:59:59	mysitecms.com	webmail.mysitecms.com	C=US, ST=TX, L=Houston, O="cPanel, Inc.", CN="cPanel, Inc. Certification Authority"
2021-01-27T17:11:57.987	2021-01-27T00:00:00	2021-04-27T23:59:59	mysitecms.com	webmail.mysitecms.com	C=US, ST=TX, L=Houston, O="cPanel, Inc.", CN="cPanel, Inc. Certification Authority"
2021-01-27T17:11:57.691	2021-01-27T00:00:00	2021-04-27T23:59:59	mysitecms.com	webmail.mysitecms.com	C=US, ST=TX, L=Houston, O="cPanel, Inc.", CN="cPanel, Inc. Certification Authority"