I had three flights that have been cancelled, all three were cancelled by me for various reasons and all three a promo code was used. I wrote in and received replacement codes for all three with an 18-month expiry date. I also wrote in on my two promo codes with July/August 2020 expiry dates and these codes were extended by six months.

Overall Air Canada has been nothing but accomodating and pleasant during this period of time. I am a firm believe its usually the approach to these situations that makes a big difference, but I have been wrong before.