[Resolved] SEO impact of corrected WPML hreflang, canonicals and sitemap output after server migration

We found a suggested workaround online:

add_filter( 'wpml_redirect_response_code', function() {
return 301;
} );

Can you confirm whether `wpml_redirect_response_code` is an official/current WPML filter?

If yes:

* Does it affect all WPML redirects globally?
* Is it safe to use on a WooCommerce Multilingual site with separate domains per language?
* Can it be limited only to WooCommerce product category archives / translated product category slugs?
* Could it negatively affect browser language redirects, language switcher behavior, currency/language cookies, hreflang, or canonical URLs?

We only want to change the redirect status from 302 to 301 for wrong translated product category slugs on the wrong country domain, for example:
`/beheizbare-handschuhe/` on the French domain → `/gants-chauffants/`.

Hi Adrey,

Thanks for your reply. Yes, Carlos is helping me with the 301 - 302 issue.
I openend this ticket for another question, but by mistake a put the 302 question in this threat.

My original question was:

Hi WPML support,

We have made several technical SEO improvements over the past days and I would like to ask how important you think these improvements are for our SEO recovery.

Context:

On 21 November 2025, our site was migrated to a new server. After that migration, our canonicals and hreflang tags disappeared from the site. We only discovered this around mid-December, and they were restored after that.

At the end of November, shortly after the migration, we saw a significant ranking drop, especially on important category pages. The rankings have never fully recovered. At the end of February 2026, almost all of our image URLs also disappeared from Google Images. We still do not know exactly what caused this.

Over the past days, we fixed/changed the following:

1. We disabled hreflang output in the Yoast XML sitemaps with:
define( 'WPML_SEO_ENABLE_SITEMAP_HREFLANG', false );

This was because the sitemap hreflang output for the WooCommerce Shop Page was wrong. It reused the current language slug on all domains, instead of using the translated slugs per language/domain.

2. We kept WPML’s normal HTML hreflang output in the enabled, because this output is correct.

3. We added a filter to remove heatperformance.com from the normal HTML hreflang output, because heatperformance.com is not a true webshop language equivalent. It is a country selector / portal page.

4. On heatperformance.com itself, we now remove all hreflang output.

5. We corrected the custom WPML language settings for “America”:

* Code: US — unchanged
* Default locale: changed from US to en_US
* hreflang: changed from US to en
* Language mapping: English

This changed the .com HTML output from:

and Yoast schema "inLanguage": "US"

to:

and Yoast schema "inLanguage": "en-US"

6. We also fixed a custom WooCommerce Shop Page H1 snippet, because some domains such as Austria showed “Heated products” instead of the correct local German title.

Current setup:

* XML sitemaps no longer contain hreflang entries.
* HTML pages still contain correct WPML hreflang tags with the correct translated URLs.
* heatperformance.com is no longer included as a normal hreflang alternate.
* heatperformance.com itself has no hreflang tags.
* Canonicals and schema language values now look correct on the tested pages.

My questions:

1. From your point of view, how important are these improvements for international SEO?
2. Could the earlier disappearance of canonicals and hreflang tags after the server migration have contributed to our ranking drop?
3. Could the wrong hreflang output in the XML sitemaps have contributed to Google confusion, even though the HTML hreflang output was correct?
4. Could these improvements, made now on 21 May 2026, still help Google regain trust and gradually recover rankings?
5. Do you see any remaining WPML-related issue that could explain why our rankings and Google Images visibility have not recovered since the migration?

Thank you.

Thank you very much, Andrey, for your look on our SEO issues!