sept 16th google update, half of traffic lost

hello, like plenty of other sites out there ours was affected big time by the sept 16th 2017 google update, within 2 days our google traffic was down 25%, and three months later we are at half of the google traffic we were getting at the start of september

anyone know what this update was all about and how to combat it?

thanks for any help

It affected in September and you came here now asking for a solution. Aren't you late ?

A) we just now realized that the traffic loss came here from this update

B) isnt that kind of how SEO works?

C) how could anyone have known what the new update was taking into account until they had months to do some guess and check to see what worked

D) it is never too late