If you have booked a flight on Aircanada.com over the past week and half or so, you’ll have noticed that you can pay to be able to reserve Emergency Row, Bulkhead and other preferred seating locations at the time of booking. Normally those seats would have been assigned at the airport or reserved for elite customers who by the way can also book this preferred seats for free depending on their status and fare class.
Pricing ranges from a low of $14 for Tango Plus fares under 350 miles to $100 for travel between two international cities via Canada.
Full details can be found here