If you are adding a Cloud plan to a router that already has Speedfusion Cloud (e.g. your router included the 1TB/1 year plan and you still have some data left), any data left from your existing allowance will be added to your new allowance, to be used by the expiration date of the new plan.

Example: You have 500GB remaining from the Cloud plan that was included with your router, expiring November 1 2021. On September 1 2021 you purchase Cloud Plan C. You now have 1.5TB to use by August 31 2022 (1 year from your new Cloud purchase).

For more details refer to the Speedfusion Cloud Expiration FAQ