On October 28th, 2016 Microsoft announced the general availability of Dynamics NAV 2017.
New and enhanced capabilities in Microsoft Dynamics NAV 2017 include:
It was also the first version to allow the usage of Extensions. Version 1 of Extensions were based on C/AL delta files and only supported minimal changes compared to version 2.
NAV 2017 was used as the foundation for Microsoft Dynamics 365 for Financials, Business Edition, which was released in the US and Canada in November. D365ffbe was just a functionally "down-scaled" version.