All DCI on mainline is by DOH. In the original release of information it was supposed to be different. It was supposed to be DL mainline(S3/DOH), parents/retirees(S3B/DOH), W/O DCI(S3C/DOH), then Contract DCI(S3C/DOH). When the new rules came into effect; Delta had changed it to all DCI's(S3C/DOH).