Egress charges for migrations hasn't been a problem since 2024 March.

from https://aws.amazon.com/blogs/aws/free-data-transfer-out-to-i...

    We believe this choice must include the one to migrate your data to another cloud provider or on-premises. That’s why, starting today, we’re waiving data transfer out to the internet (DTO) charges when you want to move outside of AWS.

    If you need more than 100 gigabytes of data transfer out per month while transitioning, you can contact AWS Support to ask for free DTO rates for the additional data. It’s necessary to go through support because you make hundreds of millions of data transfers each day, and we generally do not know if the data transferred out to the internet is a normal part of your business or a one-time transfer as part of a switch to another cloud provider or on premises.

    We will review requests at the AWS account level. Once approved, we will provide credits for the data being migrated. We don’t require you to close your account or change your relationship with AWS in any way. You’re welcome to come back at any time. We will, of course, apply additional scrutiny if the same AWS account applies multiple times for free DTO.