Program release
From AFSWiki
Program release Abbreviation is PR. When a stu decides to remove himself or herself from the program at the end of the year, in order to stay longer in the host country. PR, as opposed to ER or RTN, PRES applies if the stu releases from the program on the final day of the program. PRTN, RTN or ER applies if stu releases before the planned date of departure. Students who PR, PRES or RTN can legally remain in the USA for up to 30 days. Not all partners allow PRs.