I forgot where to find the “global notice” setting and it took me a while to find it! I can see this being a very useful tool for communicating with forum members and changing it regularly. Suggest adding a link directly on the global notice visible only to admins to edit it.
Also suggest adding a “dismiss global notice” link that everyone can see to make it go away for the rest of their session. Could look like the X used to close other notifications that popup when editing a new topic etc.