If you've got the Windows Device Recovery Tool installed on your PC, it's time to update it. After all, no one likes opening the app and finding an update when you actually have to use it.
Today's is a small update, but it's still mandatory. Version 3.8.19701 includes minor improvements to HoloLens recovery, and that's about it.
The version you'll be upgrading from is 3.7.18601, which added support for a few new devices, including the Yezz Billy 4.7, VAIO Phone Biz, NuAns NEO, and Unistrong T536. This led to Insider Preview support for the Billy 4.7; meanwhile, the NuAns NEO is struggling with its Kickstarter campaign, despite success in Japan relative to its market.
To snag version 3.8.19701 of the Windows Device Recovery Tool, just open the app and you'll be prompted to install the update. If you haven't downloaded it yet, you can grab WDRT right here.