“What that means in practice is, for example, that the adjudicator's construction of a contract clause is beyond any rational justification, or that the adjudicator's calculation of the relevant time periods is obviously wrong, or that the adjudicator's categorisation of a document as, say, a payment notice when, on any view, it was not capable of being described as such a document. In a disputed case, anything less would be contrary to the principles in Macob Civil Engineering Limited v Morrison Construction Limited[1999] EWHC 254 (TCC) ,[1999] BLR 93 , Bouygues (UK) Limited v Febrey Structures Limited[2016] EWHC 1333 (TCC) and Carillion Construction Ltd v Devenport Royal Dockyard Limited[2005] EWCA Civ 1358 ,[2006] BLR 15 ”