The Scheduled Maintenance Settings page is available from the Tool Kit Module located on the Main Admin page.

By enabling the Scheduled Maintenance page, when a user first logs into Central they will see an intermediary page.  This page mentions that scheduled maintenance, i.e. software or hardware upgrade, will take place between the dates and times shown, and displays a customizable message from the Administrator.

After the maintenance task has been completed, the check mark is removed from the enabled box, and the settings are saved.  The page will no longer be displayed to users after they log into Central.