MinIO do not by default sync metadata changes on a object version marked `REPLICA` back to source. This requires a setting in the replication configuration called [replica modification sync](https://aws.amazon.com/about-aws/whats-new/2020/12/amazon-s3-replication-adds-support-two-way-replication/).

For active-active replication, automatic failover occurs on `GET/HEAD` operations if object or object version requested qualifies for replication and is missing on one site, but present on the...

        "PartSizes": [314],
        "PartASizes": [282],
        "Size": 314,
        "MTime": 1591820730,
        "MetaSys": {
          "X-Minio-Internal-Server-Side-Encryption-S3-Kms-Key-Id": "bXktbWluaW8ta2V5",

Transition tiers can be added to MinIO using `mc admin tier add` command to associate a `gcs`, `s3` or `azure` bucket or prefix path on a bucket to the tier name.