As companies grow, their requirements with the phone system grow as well. Upgrading a subscription can be done without having to restart the PBX, and the existing subscription will be prorated. Downgrading subscriptions is possible at the end of the subscription term. Permanent licenses also need to be upgraded, where the price for the previous license will be credited during the purchase.
In order to upgrade from an existing extension-based license, customers can switch to an annual license. Those licenses will keep their permanent status for the selected number of calls. Customers may also choose to continue the maintenance plan associated with their license without the concurrent call model.