Not sure if this will get posted. I wrote a "farewell" message abut 20 minutes ago, and it has not shown up yet.
The Yahoo Groups Banner says: "Starting December 14, 2019 Yahoo Groups will no longer host user created content on its sites. New content can no longer be uploaded after October 28, 2019."
However, the "Learn More" page says (among other things): "On October 21st, you will no longer be able to upload any content to the site. To share info with members of your groups, you'll continue to be able to do so via email."
https://help.yahoo.com/kb/groups/SLN31010.html?impressions=true
Also, about an hour ago, I posted a public "thank you for the heads up" in the group that alerted me (and everyone in the group) to the pending demise of these discussion groups.
Perhaps the servers are working overtime due to the announcement. Perhaps they have shut down sooner than posted.