Tumblers, Posters, Bamboo/Maple cutting boards - USPS
Apparel - OSM (where they are all sent to Chicago then from there they are sorted to USPS for delivery)
Home Good products, Oven Mitts, Mugs, Bath Mats, Area Rugs, Journals, Mousepads, Cards, Pet products - UPS MI (UPS does the first half then USPS will deliver)
Metal Signs, Outdoor Mats - FedEx
Canvas Wall Art - UPS, FedEX, USPS, GLS
Plates, Platter, Bowls - USPS
Lifestyle Products - UPS
International orders are shipped using Asendia.
The UK mug and apparel print facility is not setup to include tracking to keep the product and shipping times low. Both of those print facilities use Royal Post and on average once shipped it can take 5-9 business days to receive.
You can always check the tracking details through the orders tab in the app.