RESOLVED [7:32pm CT]:
In addition to our failover, AWS has now resolved the incident that was causing 500 errors for some customer Deploy builds. Thank you for your patience while we awaited a resolution (incident reference can be found here: https://status.aws.amazon.com/)
MONITORING [7:17pm CT]:
We've temporarily switched to a different Elastic Container Registry region. Builds now appear to be running normally. Engineers will continue to monitor the situation.
INITIAL REPORT [7:04pm CT]:
We are investigating an issue that appears to be related to degraded performance of the Amazon Elastic Container Registry service. Engineers are monitoring AWS status and looking into potential workarounds.