To meet the requirements for data storage and retrieval, the most cost-effective solution is to store the data in S3 Standard for the first 90 days and set up an S3 Lifecycle rule to move the data to S3 Glacier Flexible Retrieval after 90 days.

S3 Standard:

Provides high availability and low latency access.

Suitable for frequently accessed data.

S3 Lifecycle Rule:

Set up a lifecycle rule to transition the data from S3 Standard to S3 Glacier Flexible Retrieval after 90 days.

S3 Glacier Flexible Retrieval offers low-cost archival storage with retrieval times ranging from minutes to hours, which meets the requirement of less than 5 hours.

Implementation Steps:

Open the S3 console.

Select the bucket and navigate to "Management" -> "Lifecycle rules."

Create a new lifecycle rule to transition objects from S3 Standard to S3 Glacier Flexible Retrieval after 90 days.

Amazon S3 Storage Classes

S3 Lifecycle Configuration