Apart from Windows 10 Build 16296 for Fast Ring, Microsoft has also pushed new builds to insiders in Slow Ring. Mobile insiders in Slow Ring get the Build 15252 while PC insiders in Slow Ring get Build 16291. You can check below for the changelog of these two builds.
Microsoft has now pushed a new Windows 10 Mobile Feature 2 preview build to insiders in Fast Ring. The Windows 10 Mobile Build 15252 can be installed now on your phones.
There are no significant changes here too. Apart from some fixes, however, there is one only change and that change