If you do not want to go through the two-week "grace" period and wish to upgrade immediately, do the following:
From within the Dashboard
Select the Websites menu option from the Dashboard sidebar.
Click on your website's name to go to the website overview.
Review the WordPress core version (WP CORE VERSION) displayed in the Summary section. If an upgrade is available an Update Available link will be visible.
Click the Update Available to open the update version dialog box.
Using the selection box choose which version you would like to update to. Depending on your website's current WordPress core version, more than one option might be available.
Click Update to confirm the update. A background job will be initated to update WordPress core to the selected version. You will receive a Dashboard notification and an email when the process is completed.
From the Pressidium WordPress Admin section
Select the Websites menu option from the Dashboard sidebar.
Click on your website's name to go to the website overview.
Login to your WordPress Administration panel by clicking the wp-admin button.
Select the Pressidium menu option from the sidebar.
Click Safe WP Upgrade.
Click the Upgrade button to update the WordPress Core.
For websites using an older version of the Pressidium mu plugin:
Select the Pressidium menu option from the sidebar.
Click the Utility tab.
Click the Upgrade button to update the WordPress Core.
