The update schedule for all of the Dynamics 365 products will soon be on a twice-yearly schedule with updates in April and October. Customers using Customer Engagement applications must have updated to the latest version of the apps by 31 January 2019, and Finance and Operations customers by 31 March, 2019. After that date, only the latest version of the online services will be supported. There’s no action for Business Central and the Talent app customers as these products are already on this update schedule.
Find an overview FAQ for Dynamics 365 Update Policies here (http://bit.ly/2yovuYF) with links to further information if required.