Possible Google Update 8th February 2020
https://www.semrush.comLooks like there is a huge shakeup in Google rankings and most of the tools seems to have picked it up on the 8th of Feb 2020: Mozcast, Algoroo, Advanced Web Rankings. AFAIK there is no official word from Google on the matter.
One site of mine seems to have picked up a bit of traffic (in GA) from this, the rest seems to be holding steady. Will need to look at the Search Console data in a few days to see what sort of impact it had.