Below is the text from an email from Microsoft.
“We’re making an update to your subscription so you can share it with more people and they can use it on more devices.
With your current Office 365 Home subscription, up to five people can use Office on 10 devices total. Starting October 2, 2018, six people will be able to use the subscription instead of five. Each person will be able to install Office on all their devices and be signed into five at the same time. That means they can use Office no matter where they are or what device they’re on.
Each person will continue to get all the benefits, including premium versions of Word, Excel, and PowerPoint, plus 1 TB of OneDrive cloud storage and more.
If you have any questions, you can find more info here and in our updated terms and conditions.
Your Office 365 Home subscription will automatically update in 30 days, so you don’t need to do anything. You’re agreeing to this update by continuing your subscription.
Thanks for being an Office 365 customer.