There are 3 promotions right now, when you transfer your credit card points to BA Avios.
1) AmEx MR => BA Avios: 30% bonus
You can get 30% more miles when you transfer AmEx MR points to BA Avios from Sep 25 - Nov 25, 2018. This is a good offer for Canadian AmEx card holders. BTW, this offer is not for AmEx Cobalt Card.
2) HSBC Rewards => BA Avios: 35% bonus
You can get 35% bonus Avios when you convert your HSBC Rewards points to Avios before Nov 30, 2018. Don't forget, if you apply HSBC WEMC before Dec 31, 2018, you can earn up to 75000 points: https://www.canadianrewards.net/2018/10/hsbc-world-elite-mastercard-75000.html
Some Terms & Conditions
3) RBC Rewards (Avion) => BA Avios: 30% bonus
If you are a RBC Avion cardholder, you can convert your RBC Rewards points into BA Avios and get 30% bonus Avios before Dec 31, 2018. And you can earn up to 20000 RBC Rewards points + FYF, if you apply RBC Avion Visa Infinite card now: https://www.canadianrewards.net/2018/02/rbc-visa-infinite-avion-25000-welcome.html