The /list command is used to view and change the server's time zone list. These time zones are automatically converted to when a time is mentioned in chat.
/list view - View the server's time zone list.
/list toggle <zone> - Add or remove a time zone.
View the Server's Time Zone List
Type /list view to view the server's time zone list.
Add or Remove a Time Zone
Type /list toggle <zone> to add a time zone to the server's time zone list.
If the time zone is already on this list, then the same command will remove it from the list.