Why does the pop3 subdomain return the hostname's SSL certificate instead of the domain's certificate?
Pop3 is not a default subdomain that cPanel configures as part of the mail service. If you would like to use the pop3 subdomain for mail, you will need to add an e-mail account to the pop3 subdomain. Once the e-mail is added, the Dovecot SNI file can be rebuilt using the following command:
After the SNI configuration is rebuilt, the pop3 subdomain will work with mail connections.