In short, there are five broad scenarios for where the Brexit negotiations could end up this month. Some are more likely than others. But as of today all are currently possible. Here they are—along with the arguments typically given in support of, and against, each scenario being realized:

Scenario 1: Deal agreed following the UK’s new proposals

The first scenario is that the UK and EU reach a deal because the EU accepts many of the UK’s new proposals.

The argument made in support of this scenario is that the EU, including Ireland (which arguably will be most impacted by Brexit given its land border with the UK), wants to avoid the costs of an alternative no-deal Brexit, and so will show new flexibility.

The argument given against this scenario is that considerations around the Irish peace process and the integrity of the EU single market mean the EU does not have flexibility to move much toward the UK.

Scenario 2: Deal agreed after UK shows flexibility

The second scenario is that the UK and the EU agree a deal after the UK shows some new flexibility in its position.

The argument made in support of this scenario is that—if the EU position is firm—the UK will compromise because it does not want to run the costs of a no-deal exit or extend the Article 50 divorce process.

The argument given against this scenario is that the UK has previously made clear its opposition to the ‘backstop’ customs provision in the current withdrawal agreement and to any deal that would undermine the economic integrity of the UK.

Scenario 3: No-deal Brexit

The third scenario is that the EU and UK cannot reach an agreement and so the UK leaves at the end of October with no deal.

The argument made in support of this scenario is that the UK government has committed to leaving the EU at the end of October and so, if a deal is not agreed, it will leave with no deal.

The argument given against this scenario is that the British parliament has passed a law (the “Benn Act”) requiring the UK government to continue negotiations with the EU—by extending Article 50—if a deal is not reached this month, making a no-deal Brexit unlawful.

Scenario 4: UK requests an extension to Article 50, but EU refuses

Scenario four is that the UK and EU fail to reach a deal, and the Benn Act means the UK asks the EU for an extension to Article 50, but the EU refuses.

The argument made in support of this scenario is that—with an extension having to be agreed by all twenty-seven EU member states—one or more blocks the agreement, because they want to bring the withdrawal process to a close and prevent Brexit impacting other EU business.

The argument against this scenario is that the EU would ideally like a deal, and wouldn’t insist on no deal against the wishes of the UK, which would make Brussels responsible for any costs of a no-deal Brexit.

Scenario 5: Article 50 is extended

The final scenario is that the EU agrees to a UK request for an extension. The UK and EU would need to agree the length of the extension.  This would probably either be short—for example, to the start of 2020—or longer—for example, to mid-to-late 2020.

The argument made in support of this scenario is that the EU has indicated openness to a further extension to avoid a no-deal Brexit, especially if the extension allowed time for a change in the current negotiation dynamics. It has been widely speculated in the UK media that a request to extend Article 50 could see a UK general election held.

The argument given against this scenario is that the UK government has been clear that it will leave the EU at the end of October.