There have been numerous demands from SNP activists, including Alex Salmond, her predecessor and former mentor, for her to hold an illegal or wildcat referendum. The First Minister has resisted those calls, but intends to bring forward a referendum Bill in the spring and then try to force the UK Cabinet to mount a challenge in the courts.

One question still cropping up in Scottish Tory circles on Wednesday night was one they would prefer not to answer: what happens if Boris doesn’t go? The immediate result would almost certainly be a significant spike in SNP support and increased threat to the maintenance of the Union with England, Wales and Northern Ireland.

That’s why they are desperate for him to resign. But if he won’t, what then? One option often trotted out, and which periodically enjoys wide support, would be for the Scottish Tory party to break away from that in the rest of the UK. It has lately been fiercely resisted, not least by Baroness Davidson of Lundin Links, the former leader.

However, if Boris stays, there is little doubt that there will be renewed pressure for the Scottish Tories to go their own way.