A company is planning to deploy a consistent workload on AWS for the next 3 years. The cloud architect suggests purchasing Reserved Instances to save on costs compared to On-Demand Instances. However, the CFO is concerned about the possibility of future changes to their instance requirements. Which feature of Reserved Instances addresses the CFO's concern by allowing the company the flexibility to alter their Reserved Instance's configurations?
Scheduled Reserved Instances
Convertible Reserved Instances
Spot Instances
Standard Reserved Instances