Every Lambda you deploy to AWS Lambda gets a version assigned. The corresponding arn would look like `arn:aws:lambda:my-region:123456789101:function:my-function:my-version`. Once you have deployed the Lambda, you register it with Restate by providing this very same arn. Now, when Restate invokes a Lambda function, it remembers the arn with which it started the invocation. So on any subsequent retry, Restate will always invoke the same arn it started the invocation with.