There's no way any deal will get past Parliament. The remainers will say it's a crap deal and we should stay; the leavers will say it's a crap deal and we should just leave with no deal in March. Neither option is acceptable to at least half the population, ergo, it's election time. That way each party will have to spell out their policy in a manifesto. Corbyn (a leaver if ever there was one) can't then hide behind the shambles that is the Tory party. Labour are just as split on the issue, with the Blairite tendency remainers and the Momentum-types leavers. The election will act as a type of 2nd referendum and we then run with the result.
BTW, all this "people's vote" bollocks can **** off. All those twats want is another opportunity to block the original referendum result. That way lies constitutional issues that will take years to resolve. We need an election to sort this once and for all.