Microsoft announced the launch of Microsoft Office Long Term Servicing Channel (LTSC) and Office 2021 later this year. Office 2021 will be available under the “one-time purchase”” model for the same price customers have paid for previous versions. Microsoft also announced that they are shortening the support lifecycle of Windows 10 Enterprise LTSC releases from 10 years down to only five years. Users who want to keep their devices on the same Windows version for more than five years are advised to switch to Windows 10 IoT Enterprise releases.”
Source: https://www.bleepingcomputer.com/news/microsoft/microsoft-to-launch-office-2021-and-office-ltsc-later-this-year/