18.2The framework for such appeals is set down in COPR Part 20, amplified by Practice Direction (PD) 20A and PD 20B. These provisions were substantially altered (and made very much simpler) by the 2015 rule changes, which introduced an entirely new Part 20 and new Practice Directions. The new framework is based around three ‘tiers’ of judges, outlined in new Practice Direction (PD) 3B.1And given their statutory definition in COPR r6. In broad terms, tier 1 judges are district judges or their equivalent; tier 2 judges are circuit judges or their equivalent (including the Senior Judge if one is appointed to replace Senior Judge Lush), and tier 3 judges are puisne (ie full) judges of the High Court or their equivalent nominated to sit in the Court of Protection. These terms will be used in this chapter, because they make explanation of the appellate structure much easier, but they will rarely be encountered in day to day practice.