> ECR 24 MiB/s (8.2 s)

> S3 115 MiB/s (1.7 s)

It's great that it's faster but absolutely, it's only an improvement of 6.5s observed, as you said, on the CI server. And it means using something for a purpose that it's not intended for. I'd hate to have to spend time debugging this if it breaks for whatever reason.