When you renew a subscription, the current subscription term is extended by creating a new term. The number of periods that a subscription is extended is defined by the Renewal Term attributed to the subscription. Use the following steps to renew a subscription.
See Renewing a Subscription and follow the instructions based on your WSDL version.
After you have renewed a subscription, you can still create amendments or cancel the subscription before the renewal term starts. See Amend or Cancel a Subscription Before the Renewal Term for more information.