At the moment, there is only one kind of ToC update: Recreating the entire ToC, getting rid of any manual changes which may have been made to it. But - it's possible the user wants to make manual changes, on the one hand, but not let the ToC become irrelevant due to typing some more content or removing some content elsewhere in the document - changes which only affect the page number, and are generally applicable without "messing up" the manual changes the user made to the ToC. I suggest we also support this partial kind of update. IIANM, Microsoft Word supports updating page numbers without recreating the entire ToC.