It is the base case. It’s the same one that was leaked 3 months ago.

Listen to anyone in the know, yellowhammer is the base case. Black Swan is the worst case, no one has seen this yet.

Here is is being reported in the pro Brexit newspaper The Times - https://www.thetimes.co.uk/edition/news/this-is-not-project-fear-its-what-we-face-after-no-deal-brexit-3p2cdq9zd