This thread is resolved. Here is a description of the problem and solution.
Problem:I have two languages on my website
 English US (en_US) - DEFAULT  English UK (en_GB)
However, despite my browser and windows being set to English UK - and clearing cookies, and using incognito mode... etc etc... It will not redirect to the english UK version of the site at all.
Have I missed something here? or is there a bug?
Solution:At the moment there is a known bug that our developers are working to fix with the language redirection and languages that use similar language codes.
Please review the following Errata Documentation
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