The Moto X Pure seems to have an upcoming soak test as Motorola has been sending out notifications to users thanking them for showing interest in an "upcoming software opportunity," and although they don't explicitly mention anything about the soak test having to do with Android Nougat, the suggestion seems to be that this is exactly what the soak test is for and that Moto X Pure owners will finally be getting the update to the new software, as soak tests are usually for bigger software updates.
Motorola doesn't detail a time frame for when the soak test might be pushed out to users, but one thing that is usually always the same is that soak tests tend to last about a week or so and if everything goes well then they begin pushing the same software out to all users with the device that the test took part on. The soak test will hit a small amount of users sometime in the near future and the hope for users with the Moto X Pure is that the software is free of any issues so that it can be rolled out to everyone. With that said, whenever the soak test actually begins, Moto X Pure owners that aren't part of it can probably expect their own software update to begin within a very short time period following the start of the soak test.
At this point in time Motorola isn't detailing any parts of the soak test, and they likely won't until they actually start pushing out the software to the select number of users who are part of the testing. When that time comes there should be at least a small set of information that explains what's included, and if it's Android Nougat then users can expect things like Multi-Window, improved Doze Mode, and more. Another thing that users will want to make note of is that if the soak test is for Android Nougat, the software download files are likely to be fairly large in size, and initiating the download on a Wi-Fi connection will be recommended. With that said, users who still have a Moto X Pure should keep an eye out for the upcoming software.