The U.K. is on course to quit the European Union when Big Ben chimes midnight on March 29, 2019. Assuming Brexit negotiations don’t break down in acrimony before the clock runs out, there’s a lot of ground to cover and Theresa May’s decision to call a snap election has already changed the timetable. Here’s the latest guide to what is coming up. April 24, 2017 Sherpa Gathering Emissaries of the 27 EU governments meet for the second time to discuss the bloc’s draft negotiating guidelines. They are officials mostly unknown to the broader public: ministers of European affairs, advisers to government leaders and ambassadors to Brussels. Even though it is the Commission that has the technical expertise to carry out the day-to-day grind of Brexit talks, national governments, represented by these officials, will be keeping EU chief negotiator Michel Barnier in check. At their first meeting, on April 11, they lent broad support to EU President Donald Tusk’s tough negotiating stance. Among the main points of the guidelines is the insistence that the U.K. will first have to make progress toward an agreement to settle its EU budget commitments—known as the bill—before any discussion of transitional arrangements and its post-Brexit trade deal with the EU can start. April 26-27, 2017 Guidelines Approved The EU’s committee of permanent representatives—the top diplomats residing in Brussels—convenes, followed by a meeting of European affairs ministers in Luxembourg the day after, to agree on the guidelines. In addition to the settlement of the financial obligations to the bloc, May’s government will also have to make progress in reaching a compromise on the status of EU citizens “living or having lived” in the U.K. and of U.K. citizens living or having lived in the EU, before its partners across the Channel agree to start talks about their future relationship. April 29, 2017 Brexit Summit EU leaders will meet to sign off on the guidelines. But that’s not enough for substantial negotiations to begin. The guidelines are only the general principles which the EU will follow in talks. These will be followed by a more detailed negotiating mandate, and working documents delineating the scope of the talks in specific policy areas. May 2, 2017 U.K. Lawmakers’ Last Sitting With the prime minister planning an election for June 8, the Houses of Commons and Lords must finish all their work on or before May 2 so that parliament can be dissolved and the election campaign can begin. It’s after this date that we can expect to see May and other party leaders return to discussions on Brexit strategy. May 3, 2017 Negotiating Mandate The European Commission will circulate a draft negotiating mandate for Barnier, which national governments will also need to approve. There could be some early contact between Barnier’s team and the British government but it will be just about process, not substance, until the mandate is approved. May 4, 2017 Local U.K. Elections An early indication of how May’s gamble might pay off comes as voters in most parts of the U.K. take part in local and mayoral elections. A huge win for the Conservative party—or signs that the opposition Labour party or anti-Brexit Liberal Democrats might make gains—could transform the general election campaign and change the way the next government approaches Brexit. May 7, 2017 Le Pen Factor The attention shifts from one election to another, on the other side of the English Channel, where it’s the second, decisive round of French presidential elections. A Marine Le Pen victory would throw the EU’s future into doubt and add a wildcard to the Brexit talks. May 22, 2017 The EU Is Now Ready Had it not been for the snap election, this was the day when talks between the U.K. and EU could have started. As it is, with Britain in the midst of the campaign, European affairs ministers will be left with the job of approving the Commission’s negotiating proposals, giving Barnier a mandate to start the process. They will also establish a working group, making sure that the Council remains in the driving seat of negotiations. The directives require approval by a qualified majority of member-states, or 20 countries representing 65 percent of the bloc’s population, and any disagreements could further delay the process. In other words, dissenting interests among member states wouldn’t necessarily serve the U.K. as they could prolong uncertainty. June 8 Election Day in the U.K. Just under a year since voters chose to leave the EU in a referendum, and just over two years since the last general election, the British electorate will again go to the polls to decide on the makeup of parliament. This time the election is framed by Brexit, with May saying that she’ll campaign to make the U.K.’s departure from the EU a success. If she wins, as predicted by opinion polls, focus will be on the size of her majority, which could determine how freely she can negotiate with the EU. June 9 Talks Can Begin Once the election is out of the way, Barnier’s team can start proper talks with May’s negotiators. Both sides hope to make substantial progress on the early issues before the summer. Sept. 24 What of Merkel? Elections to Germany’s lower house of parliament, the Bundestag, mean that meaningful Brexit negotiations might not start until late 2017. Irrespective of whether Angela Merkel is re-elected for a fourth term or Social Democrat Martin Schulz becomes chancellor, it could take until as late as November before a coalition is agreed. That shortens the U.K.’s window for negotiations substantially. Oct. 1-4, 2017 Tory Party Conference May takes center stage in Manchester at the annual conference of her Conservative Party, the first since she triggered Brexit. Those opposed to leaving the EU kept a low profile at last year’s meeting; if the negotiations aren’t going well, prominent dissident voices may be more vocal this time around. Oct. 19, 2017 EU Summit EU leaders meet in Brussels. That’s the earliest realistic date for a discussion on a post-Brexit trade deal to begin, if the bloc’s governments decide that sufficient progress has been made in the meantime in the thorny issues of the first stage of the talks: the exit bill, the status of expatriates, and the border between the Republic of Ireland and Northern Ireland. There’s no need for a final agreement on those issues by then, just a political assessment that sufficient progress has been made. Spring 2018 Transitional Arrangements Assuming enough progress has been made in agreeing on the exit terms, and the U.K.’s landing zone after Brexit, the two sides can start discussing transitional arrangements. No one in Brussels expects that all the details of the future trade relationship will have been carved out by March 2019. The ambition though is to get as far as possible in defining the framework for the future. Only then can the EU agree to build bridge arrangements toward this new relationship. Fall 2018 Wrapping Things Up Discussions on the exit deal must conclude to allow sufficient time for the European Parliament and the European Council to approve it before the March 2019 deadline. The U.K. Parliament will also debate the deal—and vote on it—although May has said a defeat there wouldn’t send her back to the negotiating table. The deal needs to include transitional arrangements. A potential free trade agreement between the two sides would eventually require national ratification procedures in each of the 27 member states, while the exit arrangement only requires a qualified majority of 27 government leaders and a simple majority of the European Parliament to approve.