To be honest, a notification in the app makes more sense to me, as with e-mails there's a higher possibility something goes wrong. Did I mention spam-filters already?

However, test results within 4 days is what makes this entire testing absurd. 4 days during I may happily infect everyone. Yeah, sure, that's protecting Canada from the the spread of Covid-19, I fully agree... NOT!

Does someone know how it works with isolation for a tourist? A resident of Canada may isolates at home. But a tourist? When you first have 2 days to take the test and then it may takes up to 4 days 'till you get a positive result, it's hard to guess where exactly you'd be at that time, particularly if you're on a road-trip. Maybe not at the address (anymore) you put in ArriveCAN. Imagine you're staying in a quite expensive hotel at the time you learn you've tested positive. Are you supposed to stay in that very hotel for another 10 days from that time on? What if the hotel hasn't availability for the entire time of your isolation? Is it permitted to change to a (maybe cheaper) place to sit out the period of isolation? To me this is a different story than to have a place for a mandatory quarantine period right after entering Canada (as for the unvaccinated). There you know you'll have to quarantine and can organize a place to do so in time.

And do you have to notify the authorities by phone or mail about where you isolate, particularly if the place is different from the one you put in ArriveCAN?