The original version of Windows 10 Fall Creators Update or version 1709 was released on October 17, 2017. Since then Microsoft has released some new feature updates such as versions 1803 and 1809. As of today, version 1709 of Windows 10 ceases to be supported by the mainstream channel (main support).
According to the official Windows Lifecycle Newsletter, Microsoft is discontinuing support for Windows 10 Home, Pro, Pro for Workstations and IoT SKUs in the Fall Creators update.
The expiration of the main support refers to the date on which Microsoft ceases to provide non-security fixes, updates, or technical assistance.
So as you understand this is the right time to update to the next available feature update.
Why; With the expiration of extended support, Windows 10 will no longer receive security updates that can help protect your computer from viruses, spyware, and other malware that may steal your personal data.
Windows 10 Enterprise and Education users will have another year of support from the company, as these versions will be supported until April 14, 2020.
Microsoft has updated the support page for version 1709 by adding the following notes:
Reminder: March 12 and April 9 will be the last two Delta updates for Windows 10, version 1709. Security and quality updates will still be available through the express and full cumulative updates packages. For more information about this change, visit blog us.
Reminder: Windows 10, version 1709, reaches support end on April 9, 2019 for devices running versions of Windows 10 Home, Pro, Pro for Workstation and IoT Core. These devices will no longer receive monthly security and quality updates that provide protection against the latest security threats. To continue receiving security and quality updates, Microsoft recommends updating to the latest version of Windows 10.
IMPORTANT: Versions of Windows 10 Enterprise, Education and IoT Enterprise will continue to be serviced for 12 months at no cost.
It is worth noting that Windows 10 version 1607 has also reached the end of support for both Enterprise and Education versions. It will be available to a small select group of users running this version of Windows on devices with Intel Clover Trail processors and Enterprise version users on the LTSC channel.