38 CFR § 3.651 - Change in status of dependents.
Except as otherwise provided:
(a) A payee who becomes entitled to pension, compensation, or dependency and indemnity compensation or to a greater rate because payment of that benefit to another payee has been reduced or discontinued will be awarded the benefit or increased benefit without the filing of a new claim.
(b) The commencement or adjustment will be effective the day following the reduction or discontinuance of the award to the other payee if the necessary evidence is received in the Department of Veterans Affairs within 1 year from the date of request therefor; otherwise from the date of receipt of a new claim.
(c) The rate for the persons entitled will be the rate that would have been payable if they had been the only original persons entitled.