I think it's because they have ads internationally but aren't allowed to have ads in the UK
You have to wonder why that was a choice, when they could serve/not serve ads based on location, instead of hard redirecting.
SEO mainly.
They prefer to use .com for international stuff and keep uk users on .co.uk
Could be a legal issue. If they have a legal requirement to not serve ads in the UK it's good to have a clean separation where they can see if the redirect is broken.
This is very annoying. I sometimes want to see how BBC is covering events from a UK perspective, but it always redirects to bbc.com.
I could switch my VPN to UK, but it never seems worth the effort.
Looks like it's a script that redirects. I have noscript and scripts are disabled by default and the site doesn't redirect me.
It’s interesting to compare bbc.com vs bbc.co.uk reporting. You should try it for a month or two and see what you think.