Dear customer,
Subscription is another selling plan, which is different with one-time purchase. Those subscription units will have limitation on usage period. If you purchase full price and one time purchase product, there is no limitation on usage period and we will not charge any additional fee.
If you purchase the subscription model and do not renew subscription, you won't be able to use the Netro cloud service for the Sprite any more. Your device will also be banned later. For more details, please refer to this link below https://www.netrohome.com/shop/plans/1
Thanks,
Netro Support