not2easy - 5:40 pm on Feb 6, 2013 (gmt 0)
The important thing is your policies. You don't say whether the customer was informed about when to expect their order, that is the question. Credit cards don't give people any special right to cancel, but a customer who has not been told what to expect four days after they order might very well cancel their order. If your site spells out what people can expect after placing an order and you send an order confirmation with the expected delivery date then it falls on them to cancel right away if they can't wait.