So as of May of this year Microsoft is allowing all Office365 (O365) business users to upgrade their local desktop/notebook machines to Windows 10. This initiative is due to all the features that Windows10 provides and how they integrate to O365. Windows7 will not be supported post January 22nd, 2020 and this is a great step Microsoft is moving people off a legacy operating system. If you have Windows devices running Windows 7 Pro, Windows 8 Pro, or Windows 8.1 Pro, your Microsoft 365 Business subscription entitles you to a Windows 10 upgrade. This only applies if you are using AD Business Azure but this is becoming very popular these days for security and authentication. This cost is $2/user and allows for Microsoft to manage AD through their services platform.
For more information on how to upgrade Windows devices to Windows 10 Pro Creators Update, follow the steps in this topic: Upgrade Windows devices to Windows Pro Creators Update.