I have heard others say that typically the IUP phone return kits ship by FedEx, but that the iPhone itself ships via UPS from China. So that may be your return kit. Or, maybe you are just super lucky!
This is from Apple:
Here is your shipment and tracking information.
Order Number: XXXXXXXXXX
Ordered on: October 27, 2017
Items to be Shipped
Shipped: Delivers Nov 16, 2017 by Standard Shipping
No signature required for delivery
iPhone X 256GB Silver Qty 1
____________________________________________
This is from FedEx:
Scheduled delivery:
Wed 11/15/2017 by 8:00 pm
Date/Time
Activity Location
11/12/2017 - Sunday
5:02 pm At destination sort facility OMAHA, NE
3:36 pm Departed FedEx location MEMPHIS, TN
11/11/2017 - Saturday
3:57 am In transit MEMPHIS, TN
2:42 am International shipment release - Import MEMPHIS, TN
11/10/2017 - Friday
11:20 pm Arrived at FedEx location MEMPHIS, TN
9:52 pm In transit LANTAU ISLAND HK
5:27 pm In transit LANTAU ISLAND HK
3:46 pm Left FedEx origin facility SHENZHEN CN
10:49 am Picked up SHENZHEN CN
11/09/2017 - Thursday
5:53 pm Shipment information sent to FedEx