When was this month?

[AndiOliversGlasses]

Internal announcement at work today referred to an award having been won “last January”.

When would you understand that to be- January 2023 or January 2024?

January 2023. I'd say "in January" for January 2024.

Same.

I'd want to clarify whether they meant January 2023 or January 2024 if the rest of the context doesn't make that clear.

Last January = 2023
January = 2024
Next January = 2025

Thanks. I agree with you all. They meant January 2024.

I was irritated by it because I knew that the article had been written by a non-native English speaker but edited and signed off for publication by a native English speaker. Wasn’t sure if was something that should have jumped out at the editor.

It was arguably more likely to be Jan 2024 given the context, but not glaringly obviously so.

Yes, I'd also assume Jan 2023 for last January when said in February 2024.

However, by September/October last January would probably mean January 2024 to me.

I'm not completely sure at what point of the year it switches over in my head🤔

Italians use "last" for anything that's past.
So "last January" for them would be 2024.