Massive changes in traffic and rankings is reported by many on Nov 8th.
Google has now confirmed there was an update
Some have asked if we had an update to Google Search last week. We did, actually several updates, just as we have several updates in any given week on a regular basis. In this thread, a reminder of when and why we give specific guidance about particular updates….
— Google SearchLiaison (@searchliaison) November 12, 2019
Many SEOs noticed big fluctuations in their sites. Some 25-40 % down in
traffic.