Another time consuming battle to fight.
With Article 50 officially signed and presented, it opens up another time consuming can of worms for the EU. In the face of it all, they have to kinda hope a key trading partner is not successful on their own as it will only encourage others to potentially follow suit.  Anyway, it will be a long drawn out ordeal – kinda like what we have seen with Greece (and continue to see with Greece).  It will take a lot of time and resources and meetings and meetings and comments and comments. You know how they all like a headline and a meeting.