Killer.... Sounds to me like you have cut your time too close. I have problems regularly where someone tells me that they are shipping something and we should have it in a few days. Unfortunately, at best, you can control your own schedule. You cannot control someone else's schedule. If he had to waut to get the things from someone else, he most likely coundn't control the delivery time to him.
We regularly order parts "overnighted", just to get them in 3 or 4 days.