Redirecting Domain to cPanel user on new WHM

You certainly could redirect to the IP URL of the "new" server, just like you're suggesting. However, remember that accesses to IP URLs are unable to have their bandwidth attributed to the site owner. So, all traffic you redirect in that fashion would essentially be unmetered bandwidth.

If that's not a concern for you, then there's not necessarily a direct problem with using that redirect. However, also be aware that some scripts/sites are not designed to be called from a different directory structure like that. Some sites *will* break and refuse to load because you're loading it from "/~username/" instead of "/".

If this is a problem that's gone on for over a week like you say, though, I'd be hesitant to advise such a bandaid fix like a redirect. You should continue to encourage the affected users to resolve the DNS caching problem with their network equipment and/or contact their ISP as necessary.

 

Sounds like you have .htaccess mod_rewrite rules or otherwise setup on the new box that's force rewriting all URLs to prefix with www.

You'd need to identify what's doing that and turn it off or adapt an exception to allow an IP URL. Since it could be any amounts of possible causes (.htaccess rewite, Joomla plugin, etc.) I really wouldn't have a solid recommendation to start with. But, it would be something like that.