I concur with what mtindor has posted; following the suggestions regarding redirection options in WHM Tweak Settings, clients could simply use the available redirects to be forwarded to the server hostname with SSL/https included and provided the installed SSL certificate is properly signed and trusted there should be no SSL-related warnings.
If a user does not use the available redirects and instead attempts to access cPanel directly via SSL/https while specifying the appropriate port number (e.g., 2083, 2087, 2096), if the domain entered does not match the SSL certificate then the user's browser may display a warning indicting it is not "trusted" because of a domain name mismatch; this is normal and to be expected in this specific situation. For this scenario I recommend advising users they may either manually trust the certificate in their browser configuration (or other configurations for mail and FTP client applications) or that they may also use the server hostname to avoid SSL-related warnings (assuming the installed SSL certificate is properly signed and trusted). The following are a few example URLs in reference to accessing cPanel, WHM, and Webmail, via SSL (with the applicable port numbers):
Code:
https://server:2083/
https://server:2087/
https://server:2096/