private ReversePath rewriteNotSrs() {
String timestamp = calculateTimestamp();
String host = mailbox.getRemotePart().smtpText();
String localPart = mailbox.getLocalPart().smtpText();
String hash = calculateHash(timestamp + host + localPart);
RemotePart rewrittenRemotePart = calculateRewrittenRemotePart();
StringBuilder buffer = new StringBuilder();
buffer.append("SRS0=");
buffer.append(hash).append('=');
buffer.append(timestamp).append('=');
buffer.append(host).append('=');
buffer.append(localPart);
buffer.append('@');
buffer.append(rewrittenRemotePart.smtpText());
return new MailAddressFactory()
.createReversePathAlreadyVerified(buffer.toString());
}