The United Kingdom has been able to open up after a majority of its population was inoculated with the AstraZeneca vaccine. 
The health risks post the second dose are extremely rare. 
There isn’t enough evidence as to the safety, potential side effects and efficacy of mixing and matching vaccines. 
There are AstraZeneca doses in storage in Canada which are about to expire at the end of the month. There are over 650,000 doses of the AstraZeneca vaccine in Canada, available at this time. Over 2 million people in Canada have already received their first dose of AstraZeneca. 
I urge the government to release the AstraZeneca vaccines to those who have received their first dose without issues, and wish to receive the second dose of the same vaccine. 
I urge the government of Canada to do this at the earliest.