The A challenged the refusal of leave to remain as a Tier 4 student, as he claimed not to have received the R’s curtailment notice of Tier 4 leave. This challenge had already been litigated through to an oral hearing in the Administrative Court and found to be unarguable. As the A adduced no new evidence and provided no fresh material, the court held that the doctrine of res judicata and the principles in Opoku applied. The A’s present claim of lack of effective service of the curtailment notice was an abuse of process. Judicial Review dismissed.