When is the Win10 system preview updated?

According to Microsoft internal news: Win10 preview version of the internal version has been updated to 9861 version. However, this version has not been released publicly, only for a small number of users. According to the latest news, Microsoft will bring the first update of the Win10 preview in the next few weeks. According to this time calculation, will it be the patch day of the next month?
Win10 system technology preview version image download: http://www.xp85.com/html/Win10P.html

According to informed sources It is revealed that in addition to this update, Microsoft seems to plan to update the Win10 preview once or twice a month. Currently, the news has not been confirmed by Microsoft. Microsoft is currently pushing the development progress of the desktop version of Cortana. The first update will not only bring stability and some problem corrections, but also whether Microsoft will bring more new features and new highlights. For example, the previously exposed notification center or IE 12 .