The EU has stated that they need to hear by close of today if any extension beyond the 12th of APril and they said they would only do that if the UK agreed the deal May got offered in which nobody of any voting stance likes.
In short, the EU is dictating Brexit direction more than the UK now.
So unless they agree May's deal, any other extension has to be voted upon.
However technically the UK could cancel article 50, then resubmit it and give an extension of upto 2 years as article 50 covers a 2 year period and in that time the end date can be earlier. Whilst technically they could do that and the EU would be powerless to stop them, it would be a complete and utter gaming of the political and legal system.
The Article 50 treaty says very clearly that unilateral revocation isn't possible. The ECJ has done what's expected for the EU and simply ripped it up, but will the other heads of state accept the treaty they all signed just being voided like that?
Probably yes - ultimately what happens in the EU is always and everywhere about politics. Written law hardly matters.
You are incorrect. The ECJ confirmed on 10 Dec 2018 that unilateral revocation is possible. Indeed the exact title of the press release from the ECJ after the judgement was "The United Kingdom is free to revoke unilaterally the notification of its intention to withdraw from the EU".
How is what I'm saying incorrect? You're agreeing with me that the ECJ voided the treaty. Here's what Article 50 says:
3. The Treaties shall cease to apply to the State in question from the date of entry into force of the withdrawal agreement or, failing that, two years after the notification referred to in paragraph 2, unless the European Council, in agreement with the Member State concerned, unanimously decides to extend this period.
The treaties cease to apply two years after the notification date unless the Council decides unanimously to extend.
The ECJ read this and said, nope, unanimous consent not required actually, the country can simply revoke it (i.e. extend indefinitely) at any time.
In short, the EU is dictating Brexit direction more than the UK now.
So unless they agree May's deal, any other extension has to be voted upon.
However technically the UK could cancel article 50, then resubmit it and give an extension of upto 2 years as article 50 covers a 2 year period and in that time the end date can be earlier. Whilst technically they could do that and the EU would be powerless to stop them, it would be a complete and utter gaming of the political and legal system.