Health Canada's strategy is to have a portfolio of vaccines that offer different characteristics. For example, the AstraZeneca vaccine has one characteristic that's very interesting, which the others don't have, and that is that the vial, once you take the first dose, can be refrigerated and used for other patients for up to 48 hours, while all three others are only for six hours—
On March 11th, 2021. See this statement in context.