Cabinet unease over open-ended customs union
Apart from Michael Gove only narrowly avoiding a bus on Whitehall as it broke up, on the face of it the meeting tonight was rather uneventful.
No decisions were taken. There were, as yet, no resignations. No-one, I'm told, even had a big strop. Honestly!
But after two years of huffing and puffing and haggling, one thing is becoming clear.
The prime minister has always said that the UK could not accept staying in the customs union.
But there are signs that the UK is considering whether to stay in an almost-identical arrangement for good, if a wider trade deal can't be done.
You guessed it, it's all about Northern Ireland again. And regular readers here will know that avoiding a return to the borders of the past has for months been the biggest headache.
In theory if, as Number 10 hopes, a super-duper trade deal can be done, then you don't have to worry about it.
But there are such doubts about that happening in time, that the backstop argument is politically vital.
Here's what might be good news for the UK.
The negotiators seem to have persuaded the EU that if the trade deal isn't done by the end of 2020, then the whole country, not just Northern Ireland, should stay in what's essentially the customs union (even though it would probably be known by another name).
This hope was set out months ago under the so-called Temporary Customs Arrangement.
There was a row in cabinet then about whether it needed to include a time limit. In the end, it did have one written into it, after threats of resignations.
Back then, the EU just would not accept that kind of arrangement for the whole country. Brussels' alternative backstop proposal would basically carve off Northern Ireland.
They have now, it seems, accepted the notion of a customs union for the whole country as part of the deal.
But they are not budging on giving that to the UK with a time limit too.
For several cabinet ministers, that's simply not acceptable. The Brexit Secretary himself is on the record saying as much.
Brexiteers have long argued that if the UK stays in the customs union, it's hardly like leaving the EU at all.
And at the meeting today, several ministers, including Dominic Raab, Liam Fox, Jeremy Hunt and Michael Gove made that concern plain, not just because there are questions about whether it's the right thing to do, but also about whether it could clear the House of Commons.
And at least one cabinet minister, Andrea Leadsom, is thinking carefully about whether she could put up with such a compromise. Essentially that's code for deciding whether to resign.
At the meeting this afternoon, I'm told the prime minister did not explicitly tell her colleagues she was planning to do this, rather she was sounding them out.
But in other briefings today, officials are understood to have been rather more clear, saying that Number 10 stands ready to accept a backstop with no explicit time limit.
None of this is at this stage being officially confirmed.
But it's clear tonight that Number 10 is considering whether what was once seen as an unpalatable step to take, is the reasonable price for a deal.
One senior government figure suggested to me months ago this was the only eventual outcome. But the prime minister's critics will come roaring out if and when she makes that clear.
PS: Number 10 won't comment officially
PPS: Those of you who have really been paying attention will know this is separate to the other big problem in the potential compromise, increasing the number of checks on goods moving between Britain and Northern Ireland.
That's a different headache for Theresa May and no less problematic.