To improve Yammer experience, Microsoft is integrating Yammer with various Office 365 collaboration tools, such as SharePoint, OneNote, Planner, and more. Because of this Office 365 integration, Microsoft has decided to retire the standalone Yammer Enterprise plan on January 1, 2017 for all Volume Licensing (VL) and Direct channels, and on July 1, 2017 for Partner channels, i.e. Syndication and Cloud Solution Provider (CSP). The 6-month extension for Partner channels adhere to communication obligation for Syndication.
Microsoft also confirmed that Yammer will continue be available through Office 365 flagship suites: Business Essentials, Business Premium, K1, E1, E3, and E5. Most customers will not be affected by this change.