I have seem a major drop in my ecommerce site almost 20K. Is this the drop with last week updates

Page one for one of our major niche keywords (about 8k volume) has remained stable for years. There was very little movement between core updates. However, just recently, Google can't seem to sit still. The top 10 are being rearranged constantly - daily, if not hourly.

Everyone is still recovering from last month's updates. This one seems more minor in comparison and thank the flying spaghetti monster for that!

One day Google is sending human traffic followed by days of massive Gbot crawling and few humans. I'm seeing other odd activity as well such as Google crawling an old online order success page from four years ago by first hitting a malformed URL and being 301'ed to the "thank you for your order" page. After a human from Google visits a product page, that product page is immediately followed by a Gbot crawl despite all the massive crawling going on.

My site has been jumping in and out of the top 50 the past two weeks.

I've registered large fluctuation before the update was completed. More than 30 keywords dropped out of SERP and then around 5th of September everything started to come back to normal and the SERP was recovered completely.

Was there any google algorithm update yesterday. My ecommerce website has been hit badly

I think most people didn't notice yet that 1 or 2 days before a holiday, and even after 1 or 2 days, the traffic usually is lower. Probably not the same in all niches, but it happens.

It dosnţ looks very large... maybe just classic oscillation