PA stands for Prefectural Advisor. The PA System is basically in place as a more local form of counsel, to discuss things or ask questions JETs wish to keep private from their COs and for working out misunderstandings or problems between JETs and their COs or Supervisors. PA's work is in addition to their normal tasks as an ALT or CIR, and they do not receive extra compensation. First years are generally not able to become PAs, but may be asked to in situations when it is necessary. As part of a PAs responsibilities, they are available to you 24/7, but your first contact should always be your supervisor, especially regarding local problems or questions.
PAs are expected to treat all JETs information with strict confidentiality, but may discuss cases with other PAs, including Japanese PAs, for consult including procedural details and Japanese language assistance.
See more information about how to get started at the Central Wikia tutorial.