Best Practices for Migrating Docker Images from Google Container Registry (GCR) to Artifact Registry with High Volume of Tags

community!

I am migrating our Docker images from the deprecated Google Container Registry (GCR) to Google Cloud Artifact Registry. I am seeking advice on best practices and strategies to handle this migration efficiently, especially considering the large scale of our Docker images.

Our current setup involves a GCR repository in the EU eu.gcr.io/my-company/ containing over 500 Docker images, each tagged more than 500 times.

We initially considered using the "mirroring" feature to transition from GCR to Artifact Registry by creating a new project in Artifact Registry with the same eu.gcr.io/my-company/ domain. However, several challenges have arisen with this approach:

1. Loss of new features: By mirroring the Artifact Registry, we cannot take advantage of the newer features offered by the Artifact Registry.
2. Inaccessibility of old images: After setting up the Artifact Registry and redirecting traffic to it, the older images in the GCR become inaccessible. Is there a way to maintain access to these older images post-migration or a strategy to re-host them within the Artifact Registry without losing their references?
3. Tooling limitations: We looked into using gcrane for the migration, but it support only migrating from *.gcr.io to pkg.dev directly. Are there alternative tools or scripts recommended for this migration type that can handle many images and tags efficiently?

Given these challenges, I’m looking for advice on:

1. The best approach to migrate from GCR to Artifact Registry considering the scale of our repositories.
2. Strategies to ensure a smooth transition without losing access to our existing images and tags.
3. Any tools or services that facilitate this migration, especially for repositories with a significant number of images and tags.

Thank you in advance for your insights and recommendations