R.J.
Major shipping has to deal with not just LOCAL weather, but trucks and planes that get stuck (so they don't have a truck to put it in, or are 3 shipments behind) from trucks and planes that get stuck in other locations. I have a girlfriend who works UPS here, and it's a common logistical probelm. Trucks snowed in in the mountians in Idaho that they need here in Seattle in order to get things moving. Ditto, when the roads open they'll have 5times the ordinary "pile" to get moving. So they'll have every shift working doubles and still not be able to get caught up. 5 days of work in 1 day is just impossible, even if they had the trucks to do it. So the "oldest" goes first. AKA the person who ordered 1day and has been waiting 5 days will get theirs before the person who ordered 1 day and has been waiting 3.
They'll refund on the wait.