38 CFR 19.51: Place of filing Notice of Disagreement and Substantive Appeal.

The Notice of Disagreement and Substantive Appeal must be filed with the Department of Veterans Affairs office from which the claimant received notice of the determination being appealed unless notice has been received that the applicable Department of Veterans Affairs records have been transferred to another Department of Veterans Affairs office. In that case, the Notice of Disagreement or Substantive Appeal must be filed with the Department of Veterans Affairs office which has assumed jurisdiction over the applicable records.