Problem:
My problem now is that I want to add en-GB as a language. When I try to add English with a code of 'uk' I get an error that 'The Language code already exists.'. I assume this is because the database is pre-populated with Ukraine as a language. This is not unreasonable, but people in the UK often refer to the country as UK not GB, and even if I could change my folder for UK English to be GB it is pre-existing as UK, so this would cost me in SEO which I cannot accept.
Solution:
Deleting a language from WPML is not a good idea.
Instead, you can go to WPML → Languages → Site Languages, press the Add / Remove languages, add the Ukraininan language, then press the Edit Languages link. This way you'll be able to "transform" Ukrainian into UK English.
