Neowin posted a story that Microsoft's Gabe Aul has announced that they are currently testing build 10136 in internal slow rings as the next candidate for the Windows 10 Mobile Insider Preview

The last potential build we heard about was 10134 just last week. According to Gabe Aul, the build felt "really good", but had an update bug, relating to upgrading, holding it back. We got to see some of the changes that are coming in a series of leaked screenshots showing graphical changes and tweaks to Project Spartan. Build 10134 even got some video treatment showing changes to settings and new pivoting gestures in the phone and alarm apps.

The last mobile build that was released to Insiders was build 10080 on May 14th, almost one month ago. This particular build had numerous new bugs which didn't allow it to be released to the slow ring, leaving slow ring insiders on build 9941.

  Windows 10 Mobile build 10136 may be rolling out to Insiders next week