James Smith, the developed markets economist at ING, notes that things are moving fast, but conventional wisdom suggests the best election strategy would be for the UK to have left the EU before voters head to the polls. 

"That favours option two - where the government reluctantly accepts the delay and presses ahead with the legislation - and this is currently what we narrowly think is more likely.

But then again, it's worth remembering that the Conservative's whole election campaign will rely on Brexit being front-and-centre in the electorate's minds when they cast their vote. Counterintuitively if a Brexit deal is ratified, but an election takes place with a lag (say in February or March next year), that might just give the opposition the space to reframe the debate away from Brexit, back to the domestic agenda (particularly economic issues) where the Conservatives are arguably more vulnerable. 

The benefit of going to an election now is that is would be harder for the election narrative to be about much other than Brexit - even if the government has failed to meet its October 31 "do or die" deadline.

Whatever the government decides, these arguments will be front-and-centre as it tries to maximise its chances at the next election."