Microsoft updated its Windows Device Recovery Tool today, bringing the version number to 3.10.24401. The new update adds support for the HP Elite x3, along with minor bug fixes.
HP's Elite x3 Windows phone isn't out yet in the United States, but it's shipping already in the UK. If you're not familiar with the device, it's the most (only?) anticipated Windows 10 Mobile device of 2016, on account of its Snapdragon 820 chipset, 64GB of onboard storage, and 5.96-inch QHD display.
It's unknown if this is a preamble to support for the device being added to the Windows Insider Program, although it seems likely. Other phones, such as the Yezz Billy 4.7, have been added to the Insider Program after being supported in the Recovery Tool. After all, users will always need a way to roll back from a Fast ring build.
You can download the Windows Device Recovery Tool here, but if you need to update an existing installation, you can simply open it and it will prompt you to install it.