last week they were only offering $10 per $50. Duluth is still having their 30% off site-wide sale. Fine print says the bonus card is useable after 12/26, but the $10 bonus card had said the same thing and I was able to use it immediately. If the $50 for $150 works now, that's some awesome savings on great clothes.
here is link to original post regarding 30% https://slickdeals.net/share/android_app/fp/605815