This week has been billed as a potentially pivotal one for UK politics. What could happen and when?

What are some backbench MPs trying to do?

In brief, to ensure Boris Johnson cannot remove the UK from the EU without a deal. They aim to seize control of the House of Commons timetable and push through a bill before the chamber is suspended at the end of the week. The planned bill has not yet been published, but one key backer, the Tory-turned-independent MP Nick Boles, said the plan would be to mandate Johnson to seek a brief extension to Brexit if, by a set point in October, he had not passed a deal through parliament or gained MPs’ approval for no deal.

How would the timetable play out?

Haste is key. The plan would be for a vote on controlling the timetable to be held on Tuesday, and then to push the bill through all stages of the Commons and House of Lords before parliament is prorogued early next week. There is speculation this could involve the Lords sitting late at night or even over the weekend to get past government delaying tactics.

Do the rebels have the necessary numbers?

David Gauke, another key rebel, has said it will be tight. However, about 15 or 16 Conservatives seem committed, despite the threat by No 10 to remove the whip from any dissenters. Even with the likelihood of a few Labour MPs voting with the government, this would seem enough.

How would the government respond?

It appears increasingly possible Johnson will take the nuclear option of responding with a call for a snap general election. Downing Street’s threat to rebel Tories of losing the Conservative whip would remove the party’s slim working majority. No 10 sources say a vote on the backbench bill would be seen as an “expression of confidence” in the government, which is ominous.

Could Johnson seek an election?

Not unilaterally. Under the Fixed-Term Parliaments Act 2011, it would require a two-thirds majority in the Commons. If the election was called for before 31 October, Labour would be expected to back the move, most likely along with other opposition parties, making the threshold straightforward. Many MPs would be expected to seek guarantees the election would take place before the Brexit deadline, with 17 October forecast as a possible date.

Who would win an election?

No one can know. Johnson would pitch the fight in openly populist terms as “the people” seeking to recover Brexit from the perfidy of remain-minded MPs, and hope to exploit Labour’s sometimes woolly position on the issue. But he would face a twin threat from the Liberal Democrats taking remain Tory votes, and from the Brexit party, for which Nigel Farage will warn a new Johnson government would simply push through a reheated version of Theresa May’s deal, Northern Irish backstop and all. We cannot tell who would win, but we do know it would be a brutal battle.