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

Results forwww.cloudflare-test.atlassian.net

Logged At	Not Before	Not After	Common Name	Matching Identities	Issuer Name
2019-09-10T12:25:50.186	2019-09-10T00:00:00	2020-09-09T12:00:00	cloudflare-test.atlassian.net	cloudflare-test.atlassian.net	C=US, ST=CA, L=San Francisco, O="CloudFlare, Inc.", CN=CloudFlare Inc ECC CA-2
2019-09-10T12:25:48.75	2019-09-10T00:00:00	2020-09-09T12:00:00	cloudflare-test.atlassian.net	cloudflare-test.atlassian.net	C=US, ST=CA, L=San Francisco, O="CloudFlare, Inc.", CN=CloudFlare Inc RSA CA-1
2018-10-15T04:56:26.471	2018-10-11T00:00:00	2019-10-11T12:00:00	cloudflare-test.atlassian.net	cloudflare-test.atlassian.net	C=US, ST=CA, L=San Francisco, O="CloudFlare, Inc.", CN=CloudFlare Inc ECC CA-2
2018-10-11T06:04:33.504	2018-10-11T00:00:00	2019-10-11T12:00:00	cloudflare-test.atlassian.net	cloudflare-test.atlassian.net	C=US, ST=CA, L=San Francisco, O="CloudFlare, Inc.", CN=CloudFlare Inc ECC CA-2
2018-10-11T06:04:28.421	2018-10-11T00:00:00	2019-10-11T12:00:00	cloudflare-test.atlassian.net	cloudflare-test.atlassian.net	C=US, ST=CA, L=San Francisco, O="CloudFlare, Inc.", CN=CloudFlare Inc RSA CA-1