In a future WIN10 “features” release, Cortana will become a separate new app rather than being integrated in the WIN10 O/S:

https://www.pcmag.com/news/369301/cortana-is-now-a-microsoft-store-app

Ever since Microsoft’s virtual assistant Cortana appeared for Windows 10 in 2015 it has been dependent on the operating system for updates. However, Cortana is set to become a completely separate service as proven by the appearance of a new app in the Microsoft Store.

As Windows Central reports, a new beta app has appeared in the Microsoft Store offering Cortana to Windows 10 and Xbox One owners. However, choosing to download and install the app right now presents you with the message, “Hi, thanks for taking an interest!” and nothing more. Clearly Microsoft isn’t quite ready to let us start using the fully-independent version of its virtual assistant.  By splitting Cortana from Windows 10, Microsoft will be able to more quickly update the app, fix bugs, and improve Cortana’s functionality and feature set.