Drop in Traffic and Rankings after Migration + Google Core Update

Hi All,

I have an online shop + blog with 300+ articles. We’re ranking #1 on most of our keywords, and we generate 1.5m pageviews per month. We’ve recently migrated our blog to a new CMS platform which was created under a subdomain altho the articles are of the same url structure. The migration took place when Google had its core update in August 2023. After the migration and the core update, our rankings dropped drastically and pageviews went down to 50-100k a month.

Could the subdomain be the reason?
The articles are loaded in the cms under the subdomain www. blog.example.com but the URL of the article is under the main domain so that’s http://www.example.com/subdirectory/article-slug basically the article URL before system migration is the same URL after migration

When the migration took place, not all Metakeywords where unfortunately migrated but we updated them within 2 weeks span. All URL, content, and metadescription where kept the same. It’s been 3 months now but I can’t see our rankings going back to peak high.

Could it be just because of the Google Core Update? All technical SEO, on page SEO, off page SEO are OK, and GA4 is tracking the pageviews correctly.

Do you have any suggestion of what things we need to check or to improve to gain back our ranking?

cscixjnky said:

Could the subdomain be the reason?
The articles are loaded in the cms under the subdomain www. blog.example.com but the URL of the article is under the main domain so that’s http://www.example.com/subdirectory/article-slug basically the article URL before system migration is the same URL after migration

Click to expand...

This is the reason, Try to restore as it was before, and submit the previous site map at google search console again.

cscixjnky said:

The articles are loaded in the cms under the subdomain www. blog.example.com but the URL of the article is under the main domain so that’s http://www.example.com/subdirectory/article-slug basically the article URL before system migration is the same URL after migration

Click to expand...

this is so confusing... and I have so many questions that I don't even know where to start asking...

1. Did you do the 301s properly?

2. Are you having any 404 pages (due to incorrect / non-existent 301s, but not only)?

3. What do you mean that the articles are "loaded" in the CMS, but they are "under" the main domain? Loaded how? If they're published on blog.example.com then their URL should be blog.example.com/article-slug and whether or not you want to 301 these URLs to example.com/subdirectory/article-slug is up to you, but in this case the subdirectory would need to be created, otherwise you're going to get 404 pages and that's definitely one reason for ranking drops. But why would you move the articles to a subdomain but display their URLs as subdirectory?? I don't understand...

cscixjnky said:

not all Metakeywords where unfortunately migrated but we updated them within 2 weeks span

Click to expand...

what are these??

cscixjnky said:

Could it be just because of the Google Core Update? All technical SEO, on page SEO, off page SEO are OK, and GA4 is tracking the pageviews correctly.

Click to expand...

if things are right, like you say, then yes, it's most definitely a google update issue. Although, I did hear of cases in the past when people have changed CMS and rankings have taken months to restore, but this was over an year ago I think... But it's possible

cscixjnky said:

Do you have any suggestion of what things we need to check or to improve to gain back our ranking?

Click to expand...

I would still run a site audit because I have a feeling that you've left with some 404 pages after this convoluted maneuver with subdomains and subdirectories, you've probably messed up / didn't do some 301s

Just configured 301 redirect previous URLs to new URLs
Or restore your website to previous CMS.