38 C.F.R. § 20.1406 – Rule 1406. Effect of revision; discontinuance or reduction of benefits.

(a) General. A decision of the Board that revises a prior Board decision on the grounds of clear and unmistakable error has the same effect as if the decision had been made on the date of the prior decision.
(b) Discontinuance or reduction of benefits. Revision of a prior Board decision under this subpart that results in the discontinuance or reduction of benefits is subject to laws and regulations governing the reduction or discontinuance of benefits by reason of erroneous award based solely on administrative error or errors in judgment.
(Authority: 38 U.S.C. 7111(b))