Microsoft plans to release a big update for the Xbox One later this year, but that means members of the Xbox Preview program will have to wait a bit longer to try it out. The next build for Preview members won't be released until late May or early June.
Usually, new preview updates are released on a monthly basis, with the last one rolling out to members of the testing program in early March. However, Microsoft's Mike Ybarra has confirmed on Twitter that will change for the next update:
Win10 Anniversary Update announced at //build will have key gaming features, so next Xbox system update goes to preview end May/early June.— Mike Ybarra (@XboxQwik) April 12, 2016
As Ybarra stated, the reason is the big Windows 10 Anniversary Update that will also be released for PCs and smartphones later this summer. The update will bring, among other things, the Windows Store and background audio over to the Xbox One.