Over two dozen updates to some Canadian coins in my collection were listed as being done on 6 Sept. I did not do these updates. Was this something internal? Sorry if this has been already addressed.
Yes, changes in the catalog, updating and splitting of several pages. Described in this thread: https://en.numista.com/forum/topic133870.html A couple of 1 cent coin pages were split. Your coins were moved from the old pages to the new pages.