Are you alluding to the fact that Parliament would also have to amend the European Union (Withdrawal) Act 2018 to give effect to any extension of the A.50 as requested by the PM under  the European Union (Withdrawal) (No. 2) Act 2019?

I'm sure if there is a majority for one change, there will be a majority for the other. I'm also sure BoJo will seek to find some legal loophole whereby he will be able to avoid the provisions of either.

What also seems in little doubt is that a no-deal Brexit will be legally chaotic and there may not be a Parliamentary majority for all sorts of enabling legislation which will be required to give effect to a proper transfer of powers from the EU to the UK.

Just the sort of legal chaos beloved of disaster capitalists...

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