I have a family friend that was a lower teir manager for a company, that was contracted by Verizon to facilitate the last few launches. I hardly ever chime in, but here it goes. The warehouses are stocked by now, usually 2 full weeks out they get loads of phones on pallets and more continuously roll in. They're grouped by shipping region. Most warehouses are east coast. The company that does the warehousing does other items besides phones, and the space is leased for whatever length of time. The company simply acts as a middle man from the carriers warehouse to the delivery carrier. They are sorted and grouped, that is where your track number originates. They are picked up by tractor trailer and brought to major hubs, sorted already for the most part. If they go out early, it's because the carrier lease is expiring in the warehouse, or they are out of room... It's frowned upon, but it does happen. Also it's more frequent for smaller carriers like T-Mobile, because they get smaller warehouses due to expected orders and size.