UPDATE: We've learned that Kate's 'do is actually a faux bob. (And a very good one at that!)
"Kate has sported the 'faux bob' in the past—she loves it," Upton's stylist, Bryce Scarlett, tells E! News. "This time Kate wanted people to think it was real. We also did this look for Halloween a few years back when she dressed as Marilyn Monroe."
Scarlett often documents Upton's hair transformations on Instagram, including her most recent style: Loose, shoulder-length waves. To get the faux bob look, Scarlett recommends starting with a layered haircut: "You have to first section off the top portion of the hair and divide it into a U-shape from ear to ear. [Then] gather all the hair underneath and create as little volume as you can by either braiding into cornrows or twisting the hair towards the nape of the neck," he said.
"I strategically place the pieces within the lower section of hair. Once the pieces are in you let down the top portion and style accordingly."
Even better? Kate's look can be recreated in under 45 minutes.