Changing a package for any cPanel user is very simply and can be done on WHM panel.

1. Log in to WHM panel;
2. Choose the button “Account Functions” on the main menu;
3. In the next menu choose “Upgrade/Downgrade an account” button;
4. Choose a user from the list and press “Modify”;
5. You will be able to see package list and choose a new one. Then press “Upgrade/Downgrade” button.

The package is changed immediately.