On the appeal point, as I understand it there is a right of appeal from the independent panel that will decide the case to an independent appeal board. That is an appeal either on the merits, on a point of law or against sentence (as I read rule W62).
The next avenue of challenge (I deliberately refrain from using the word 'appeal' in this context) is via arbitration - rule X3. As I read that, it basically limits challenges to an Appeal Board's decision to points of law (including a challenge that the decision below is Wednesbury unreasonable).
It is from that arbitration that there can be no further appeal on a point of law as rule X37 makes clear. (Perversely, the rule then goes on to talk about a challenge to the arbitration award, but presumably rule X37 would be its defence to an appeal under the Arbitration Act.)
So, in layman's terms, there is a right of appeal against the decision, and there is a further 'appeal' on a point of law, but no appeal beyond that. Do you agree with that?