A big red box displaying "Out Of Date" appears on the Wiki Plus page
Product & Version
Version: 2.X.X and below
If the page has not been renewed by the page owner and the expiration period has passed, users viewing this page will see an "Out of date" label.
The box appears when the Life cycle date is over. Each Wiki page has the life cycle property. It can be found on the bottom of the edit screen.
Only page owners or knowledge trustee can change this setting.
You can disable Life Cycle alert for selected WikiPlus site or entire Site Collection
WikiPlus site administrator can go to "KWizCom WikiPlus management" (through Site Settings) and uncheck "Enable life cycle" checkbox.