You can set up a playlist to allow for last-minute global changes by associating referenced pages to primary events. In this use case, a page is 'added by reference' to the playlist, meaning the originating page, which remains in the Page Pool, holds the actual data. All referenced pages are merely pointing back to the originating page for which data to show on air.
When the content of the page has changed, either in the Page Pool list (Left panel) or by double-clicking on one of the referenced pages in the actual playlist, all occurrences in all playlists in the current channel are changed both retroactively and henceforth.
To create a referenced page
Preview the page in Page Editor from the Page Pool.
Edit the page.
Press and hold ALT + drag and drop the page to the playlist.
The page acquires the following icon: