Danny Sullivan from Google has confirmed that this January 2020 Core Update is global and pretty much all core updates are global – as we knew already. But it is good to have another confirmation that this past update is a global release.
That means this past update impacts all searches in all regions and in all languages – not just US/English.
Here is Danny Sullivan’s confirmation:
It’s a global update. It has (and does always unless we say otherwise) rolled out globally.
— Danny Sullivan (@dannysullivan) January 16, 2020
So from now on if Google doesn’t say it is not a global release, it will always be a global release – unless Google forgets to say otherwise. 🙂