Traffic Went from 30K to 15K Overnight on April 7th - Help Please

[jrizzoam1]

One of my clients lost half of their organic traffic overnight on 04/07. I'm trying to figure out why. Any perspective is much appreciated.
Here's what I do know:

•   No apparent fluctuations across algorithm trackers
•   No drop in number of referring domains
•   No drastic changes in keyword search volume
•   Many pages are affected rather than one URL
•   XML site map does not look broken
•   No reported manual actions or security issues
•   We've been their sole SEO provider for about 2 years

What am I missing?

[sophiawils59]

Can you share a link of your website? So, I can share the best of my knowledge to resolve your issue!!!

[digitalludhiana]

how about the keyword ranking? maybe it's a penguin algorithm penalty by google? not sure about that though, but I have read if it's a penalty then if your keyword is on the top then it will drop down to 100+ ranking numbers.

[mandiradebnath]

What type of offpage work you did recently? May be Google has found some irrelevant work or spam link for your website.