A private letter ruling is binding on the Comptroller for a period of 7 years from the date the private letter ruling is issued unless void, modified, or revoked in accordance with the provisions of Regulation .07 of this chapter. A private letter ruling is a determination of the Comptroller only as to the transaction that is the subject of the ruling. A petitioner is not bound by a private letter ruling. A petitioner’s failure to follow a private letter ruling may be considered in determining whether interest and penalty should be reduced or abated for reasonable cause in any subsequent challenge of an assessment or denial of a refund on the issue covered by the private letter ruling. A private letter ruling may be used as evidence of a petitioner’s knowledge or intent in a subsequent proceeding. The Comptroller may use information submitted in a petition for a private letter ruling for subsequent audit purposes.