Some salutary lessons here (I wonder if the taxpayer now has a double taxation problem on c£400k income taxed in the company that cannot now be recovered as suggested in para 38 and if so perhaps he can sue his advisors). (Due to the cricket aspect one might even call this a "test" case.)
I'm not sure why taxpayer's counsel accepted (or at least did not appear to argue per para 14) that the contract (with the PSC) had no tax advantages, as that admission proved fatal (per paras 48 & 59 et seq re court's discretion on rectification remedy*) when combined with the rectification deed and presumably was incorrect for the usual reasons (unless IR35 applied).
The advisor who recommended the deed of rectification may be on the hook, as per para 66 that meant there was nothing in issue to resolve re rectification remedy given there was also "no tax advantage" in issue. (Although there seems to have been nothing wrong in principle in them doing another rectification deed at the trial to cancel the effect of the previous deed of rectification and handing this up to the judge if they realised which way the wind was blowing there so to speak assuming estoppel does not prevent that**.)
Interestingly the judge is the author of "Rectification: The Modern Law and Practice Governing Claims for Rectification for Mistake", so a successful appeal seems unlikely.
* despite the rectification deed, had a tax advantage purpose been evidenced for the 2011 contract, it seems rectification would have been allowed, since there would have then been a question to be resolved between the parties as to the effectiveness of that purpose when combined with the rectification deed.
**indeed, I'm not sure what prevents them doing that now per this case re post judgment contractual changes https://www.bailii.org/ew/cases/EWCA/Civ/2020/687.html or possibly arguing rescission of that rectification deed for mistake!