7 C.F.R. § 29.132
An inspector, sampler, or weigher, when authorized by the Division, may of his own initiative, or upon the request of an interested party, review for the purpose of verification or confirmation any tobacco which he has certificated, and any supervising official may review the work of any inspector, sampler, or weigher: Provided, That such review shall not be made if the ownership of the tobacco involved has changed since the date of certification, unless there is intimation or evidence of deterioration or of irregularities or fraud in connection with the certification or sampling. When such review discloses an error in the certification, the inspector, sampler, or weigher concerned, or supervising official shall immediately correct the error by making an appropriate change in the certificate or by canceling the certificate and issuing a new certificate in lieu thereof. Any correction made on a certificate shall be initialed by the issuing official or by the supervising official. When a new certificate is issued for a lot of tobacco, the old certificate and copies thereof shall become null and void and shall not thereafter be used to represent the tobacco described therein.
7 C.F.R. §29.132