12 Pa. Code § 145.55
The evaluation agency shall approve amendments to the building system documentation submitted to it by the manufacturer if the building system documentation, as so amended, conforms to the applicable requirements of the applicable codes and standards adopted under §§ 145.41, 145.42 and 145.44 (relating to adoption of standards; alternate standards; and adoption and effective dates-code amendments). Approval of amendments to building system documentation shall be evidenced by the signed stamp of the evaluation agency as provided in § 145.52 (relating to approval of building system documentation), with the additional requirement that the stamp shall show both the date of approval and the date after which the industrialized housing or housing components described in the building system documentation shall be manufactured under the building system documentation as so amended. Approvals of amendments to building system documentation may be by oral authorization by an officer or employe of the evaluation agency, but in the event the approval is subsequently evidenced by affixing the signed stamp of the evaluation agency to the amended sheets of the building system documentation within 10 days after the oral authorization. At the same time that the evaluation agency affixes its stamp on the approved amendments to the building system documentation, it shall prepare and distribute to the manufacturer and to the Department one copy of the amendments and supplements to the Building System Approval Report and the Building System Approval Summary as may be necessary so that the Report and Summary will accurately reflect the amended building system documentation and will continue to meet the requirements of § 145.54 (relating to Building System Approval Report and Summary).
12 Pa. Code § 145.55
This section cited in 12 Pa. Code § 145.56 (relating to amendments to building system documentation following changes in standards); and 12 Pa. Code § 145.64 (relating to modification after certification).