"Later today, we are releasing a broad core algorithm update, as we do several times per year. It is called the September 2019 Core Update. Our guidance about such updates remains as we’ve covered before. Please see this blog for more about that:"
https://webmasters.googleblog.com/20...e-updates.html
https://www.seroundtable.com/google-...day-28267.html
Best wishes and keep us posted on the effect it's having on your sites.