Apple is still shipping by Air. I doubt there is 30 days of phone inventory, more like 1-2 weeks. They are keeping their supply below 4 weeks, as part of lean

Apple is still shipping by Air. I doubt there is 30 days of phone inventory, more like 1-2 weeks. They are keeping their supply below 4 weeks, as part of lean manufacturing. Thus their turnover in supply is less than the amount of time it takes for a shipment to cross the ocean. This might still be doable, but demand shifts would mean that some models that are suddenly more popular (Eg: the white vs gold colors) would cause outages. The goal is zero supply- the phone arrives at the store just as the customer spontaneously walks in to buy it. That would be most efficient.