Thanks for the question!
We haven't done the analysis on that yet. We did look at how many people reported paying duties (we rely on reports from customers and actively asked, but don't have the data from the tracking link or other data points). And we've found that about 10% of people have to pay duties.
I would think that there is no correlation between the size and change of duties paid. But if there is, I think it wouldn't be 3 times as likely.
In our experience there is no delay when you need to pay duties.
But I invite our Canadian customers to of course help with answering this question