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Doing a simple search on Google - allowed me to find that the KrisFlyer "Saver Award" between Zurich and North America is 75,000 miles in Economy.
They do not have a Premium Economy option to search. That would be 450,000 for 6 people.
There is no way there would be 6 seats in Premium Economy available as reward seats on an Air Canada Flight. (Not even to Aeroplan Members!)
There may be 6 seats available in Economy.
Last edited by yyzflyingfr; Mar 20, 2015 at 11:40 am
Reason: Calculation of 450,000 miles