A company's expense tracking application gives users the ability to upload images of receipts. The application analyzes the receipts to extract information and stores the raw images in Amazon S3. The application is written in Java and runs on Amazon EC2 On-Demand Instances in an Auto Scaling group behind an Application Load Balancer. The compute costs and storage costs have increased with the popularity of the application. Which solution will provide the MOST cost savings without affecting application performance?