Hi Rick! I know it's only a part of the toolchain needed to support the migration, but multi-arch Docker image support for Amazon ECR is definitely on our immediate roadmap.

heh, I've had a very fun experience with spotinst.com — my a1 spot instance went down and that service couldn't restore it because it did not label the AMI as arm64. Reported that to them, got a couple acknowledgements but haven't heard back in a while, so presumably this is still not fixed.