North South
I think I read somewhere that an allowance of 10% above the 1,799m figure could be allowed at the discretion of the CAA, which fits the Lydd case. Perhaps it applied only to aerodromes which had TODAs greater than 1,800m when the rule came into being, I really don't know.
I long since gave up trying to explain or understand some of the decisions made by the CAA over the years.