This article addresses changing the shared IP address for cPanel accounts. This is the address that will be used for new accounts that are not assigned a dedicated IP.
Log in to WHM and navigate to the following location.
Home > Server Configuration > Basic WebHost Manager Setup
Change the following setting to the IP you'd like to use.
The IPv4 address (only one address) to use to set up shared IPv4 virtual hosts.
Move any sites using the old shared IP to the new shared IP using the steps in the article below.