// configured expiry and the duration until the certificate itself
	// expires.
	// We must not issue credentials that out-live the certificate.
	if validUntil := time.Until(certificate.NotAfter); validUntil < expiry {
		expiry = validUntil
	}

	// Associate any service accounts to the certificate CN
	parentUser := "tls" + getKeySeparator() + certificate.Subject.CommonName