PHP 7.4 has been out for a bit, but until very recently it hasn't been widely available under cPanel. This is changing soon and we're soon going to be deploying PHP 7.4 across all systems.
Note that PHP 7.3 will remain the system standard for some time, but once this is complete you will be able to switch to PHP 7.4 via cPanel in the usual way should you wish! (Instructions can be found in the knowledgebase!)
Sunday, July 5, 2020