There are 3 broad options:

1. No deal Brexit
   
2. Negotiated Brexit deal
   
3. Remain

The EU Council and Commission would much prefer 3 and , failing that, 2. I is the doomsday scenario.

If May negotiates a deal and campaigns for it in an election and loses,  and Corbyn wins by opposing it, then that deal is off the table.

There are then three options:

1. No deal Brexit
   
2. A re-negotiated Brexit deal
   
3. Remain

I am suggesting there will be little or no appetite for 2. Time is running out and everyone if fed up with Brexit. Unless Corbyn takes a significantly different approach (membership of Single Market or Customs Union) there will be little appetite (and time) to renegotiate. Why would the EU give Corbyn a better deal than May when so many EU governments are right wing?

So we are down to options 1 and 3 and this may be the binary choice on the second referendum ballot paper.

In that case many voters may vote for no deal because they are angry at being asked a second time and fed up with the whole business. It would also be humiliating for the UK to have to crawl back to the Council saying "please can we have our A.50 letter back?"

The EU elite (forget you and me) would much prefer option 3 to option 1. So they offer Corbyn the option of the UK re-joining a much reformed EU. Corbyn can claim to have negotiated "a better deal for Britain". Voters can feel they are being offered a better choice and the whole process has not been in vain. The EU gets to re-define itself somewhat and do stuff most of which it would have wanted to do anyway.

Everybody wins. The only question is whether the right wing majority on the Council will be able to agree a package of reforms which can credibly be marketed as a significant reform of the EU to Labour and UK voters more generally.

Brexiteers will obviously shout foul and claim the reforms are insignificant or actually make the EU worse. That will not be that hard a sell to voters who distrust Corbyn AND the EU.

But the Brexiteers will also have to spell out the implications of a no-deal Brexit much more clearly. The EU will also have to say that just as Brexit means Brexit, No deal means no deal. No flights. Food shortages. Medicine shortages.  A far cry from the first referendum:
.

At least no one will be able to claim they didn't know what they were voting for.

Index of Frank's Diaries