38 CFR § 21.412 - Finality of decisions.
(a) Facility of original jurisdiction. The decision of a VA facility in a given veteran's case:
(1) Will be final and binding upon all field stations of VA as to conclusions based on evidence on file at that time; and
(2) Will not be subject to revision on the same factual basis except by duly constituted appellate authorities or except as provided in §§ 21.410 and 21.414.
(b) Adjudicative determinations. Current determinations of line of duty, character of discharge, relationship, and other pertinent elements affecting eligibility for training and rehabilitation services or payment of subsistence allowance under Chapter 31, made by an adjudicative activity by application of the same criteria and based on the same facts, are binding upon all other adjudicative activities in the absence of clear and unmistakable error.