Borderfree shipping/duty question (backorder)

Over the Black Friday weekend, Eddie Bauer had a 40% off everything online and in-store (this was for yesterday I think, prior to that it was 30% off online and 40% off in-store). I ordered myself another pair of my jeans that I love from there and got them for 40% off. Sweet. The website said that they use the ‘Borderfree’ service which allows them to calculate the duties/tax etc and then you are not hit with a bit duty bill later one. Fine. My jeans turned out to be on backorder (just until Dec 14) and when the total came up on the Borderfree site, no duty was calculated! I am assuming there would be duty on something that came out to $48. It definitely had duty as one of the price categories (total, shipping, tax, etc) but it was coming up as $0.00. To be fair, the site did say that my credit card wouldn’t be charged until the item is actually available for shipping. So here’s my question – do you think duty might still get charged on there and they just didn’t calculate it now because the item isn’t actually being shipped yet?? I wish I knew how much to expect… I’m thinking that even with duty, it should still come out to less than the regular full price ($79.95). The total with shipping was $58, I think. I can’t imagine there would be $20 duty?? Meh. The ship has sailed as I have put in the order, but I’m just wondering what is up with the duty not being charged… Any ideas?? Ever order anything on backorder??

TIA!