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

Results fora2.alezale.com

Logged At	Not Before	Not After	Common Name	Matching Identities	Issuer Name
2021-03-29T20:04:43.354	2021-03-29T19:04:43	2021-06-27T19:04:43	a2.alezale.com	a2.alezale.com	C=US, O=Let's Encrypt, CN=R3
2021-03-29T20:04:43.097	2021-03-29T19:04:43	2021-06-27T19:04:43	a2.alezale.com	a2.alezale.com	C=US, O=Let's Encrypt, CN=R3
2021-01-27T23:02:29.082	2021-01-27T22:02:28	2021-04-27T22:02:28	a2.alezale.com	a2.alezale.com	C=US, O=Let's Encrypt, CN=R3
2021-01-27T23:02:28.873	2021-01-27T22:02:28	2021-04-27T22:02:28	a2.alezale.com	a2.alezale.com	C=US, O=Let's Encrypt, CN=R3
2020-11-28T00:08:26.417	2020-11-27T23:08:26	2021-02-25T23:08:26	a2.alezale.com	a2.alezale.com	C=US, O=Let's Encrypt, CN=Let's Encrypt Authority X3
2020-11-28T00:08:26.129	2020-11-27T23:08:26	2021-02-25T23:08:26	a2.alezale.com	a2.alezale.com	C=US, O=Let's Encrypt, CN=Let's Encrypt Authority X3