It's your right to cancel at your discretion as soon as the 4-day period is up. If you haven't heard anything from the seller and have tried at least 1 PM attempt (I recommend this for the sake of cordiality, since you never know what's going on in someone's f2f life), cancel away!That being said, be sure to read a vendor's profile page for their policies as well. For me personally, I'm only able to ship Mondays and Fridays (pre-commute and post-commute because I work out of my city during the week and do not have product at that time), and it's made very clear on my profile page that the cutoff time for shipments is the night before (because I usually have to package at like 4 in the morning before I hit the highway). So if a buyer orders at 8am on a monday morning, it's not going to get shipped until after I get back from work on Friday, which is usually the afternoon, which means there will be a short stretch where it's Past Due. Big pet peeve of mine is when I package something up and go back to mark "in transit" on my way out the door and the order has been cancelled. Not the buyer's fault per se, but it's still a pain in the ass.Anarcho47