Possibility 2a: She loses the vote of No Confidence, and the Conservatives replace her with someone more anti-EU than her, who goes for No Deal. Which splits the Conservative Party, triggering a new General Election. The victor quite possibly beats George Canning's record for shortest tenure of Prime Minister (119 days).
Possibility 2b: She loses the vote of No Confidence, and the Conservatives replace her with someone less anti-EU. Which almost certainly leads to a second referendum.
When was the last week of politics as exciting as this?
Original post on Dreamwidth - there are comments there.