This is really just politics over science at this point because some people are upset of seeing videos of people at the airports. I feel if they wanted a testing requirement, it should have been introduced 6 months ago.
I want to know about transit, in 3 scenarios:
1. International to International
2. International to US (especially as this is now entering Canada and then proceeding to US departures as the US transfer path is not always open anymore)
3. International to International with a domestic connection in between (i.e. Canadian citizen, flying Country A - Canada City A - Canada City B - Country B).
Also does the test have to be from the country you are embarking from? Can you use the same test for multiple entries within the validity period.
Asking all of this for a friend of course...