You WILL NOT, repeat NOT, be able to renegotiate the Withdrawal Agreement during an extension.
How do we know this?
1/quick thread
Hard to believe, but after all this time, this torrent of verbiage, they still don't get the basics. /2
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file:///H:/Downloads/UKEUextension%20(1).pdf
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But a long extension is not a fix in itself. It will not 'fix' the deal. It will only give time (if EU grants it) for the UK side to try and reach a consensus on way forward.
I hear you screaming already. 6/ENDS