Interesting... not posted or talked about anywhere, and not mentioned on Aeroplan.com:
https://www.aeroplan.com/en/collect/air_air_canada.jsp
Paging Andrew Yiu:
1a) What does the introduction of fares such as "P" to international routes represent?
1b) Is this an introduction to Tango fares on int'l routes?
2) Does "P" earn 100% status miles on international flights?