Thanks again for this. As expected, there are substantial differences between BC/ON and Atl (or the rest of Canada). This is reflected in the epidemiology: MB, SK, and Atl haven't had major amounts of COVID-19 introduction via intl travelers, which BC and ON certainly have...
Line-by-line: this shows BC has at all times had more than double the rate of US residents entering, relative to Atl. US point prevalence varies widely but is likely 10x-20x BC's depending on the state...
BC and ON to have 5-6x the rate of residents entering from other countries. The risk of this varies by source country, of course...