Anthropic Fable 5.1 Appears to Have Entered the AWS Backstage: Model ID Changed from 400 to 404

Dynamic Beating AI News: Amazon Bedrock has started returning a 404 "Model not found" error for the suspected Fable 5.1 model ID (the name specified in the API).

Even though an incorrect model name still results in a 400 error, Fable 5.1 now triggers a 404. According to AWS error code definitions, this indicates that Fable 5.1 has entered the Bedrock backend, and preparations for deployment are underway.