How are NSL doing? It is nearly a month since the enforcement contract started. Surely they must be adhering to its terms and getting their papers together for the final stage contested parking tickets?
Here is a little table of the appeals which were allowed, thus the motorists did not have to pay the tickets that were issued, and the ones which were refused and so they did (only one, a blue badge that was supposedly not displayed; the evidence of the traffic warden was preferred on this occasion).
On the face of it a pretty dismal performance as pretty much all of the tickets will have been cancelled for lack of evidence (I don't have the time to look at all 55 and only checked a sample).
What is clear given the current shambolic state of enforcement within NSL as that if you get a parking ticket and NSL (on behalf of Barnet Council) reject your informal representations (what we might call an appeal but simply an email or a letter) and then reject your formal representations (or formal appeal - which can be on the same grounds) it is well worth taking your case to PATAS. When NSL / Barnet Council say "No" they mean "Can we get this innocent motorist to pay because it is less trouble than appealing".
Please keep on appealing at every stage (unless you know you were completely in the wrong and don't have a coherent argument that stands any chance of winning).