38 CFR § 19.52 - Time limit for filing Notice of Disagreement, Substantive Appeal, and response to Supplemental Statement of the Case.
(a) Notice of Disagreement. Except in the case of simultaneously contested claims, a claimant, or his or her representative, must file a Notice of Disagreement with a determination by the agency of original jurisdiction within one year from the date that that agency mails notice of the determination to him or her. Otherwise, that determination will become final. The date of mailing the letter of notification of the determination will be presumed to be the same as the date of that letter for purposes of determining whether an appeal has been timely filed.
(b) Substantive Appeal—(1) General. Except in the case of simultaneously contested claims, a Substantive Appeal must be filed within 60 days from the date that the agency of original jurisdiction mails the Statement of the Case to the appellant, or within the remainder of the 1-year period from the date of mailing of the notification of the determination being appealed, whichever period ends later. The date of mailing of the Statement of the Case will be presumed to be the same as the date of the Statement of the Case and the date of mailing the letter of notification of the determination will be presumed to be the same as the date of that letter for purposes of determining whether an appeal has been timely filed.
(2) Special rule in certain cases where additional evidence is submitted. Except in the case of simultaneously contested claims, if (i) a claimant submits additional evidence within 1 year of the date of mailing of the notification of the determination being appealed, and (ii) that evidence requires, in accordance with § 19.31 of this title, that the claimant be furnished a Supplemental Statement of the Case, then the time to submit a Substantive Appeal shall end not sooner than 60 days after such Supplemental Statement of the Case is mailed to the appellant, even if the 60-day period extends beyond the expiration of the 1-year appeal period.
(c) Response to Supplemental Statement of the Case. Where a Supplemental Statement of the Case is furnished, a period of 30 days from the date of mailing of the Supplemental Statement of the Case will be allowed for response. The date of mailing of the Supplemental Statement of the Case will be presumed to be the same as the date of the Supplemental Statement of the Case for purposes of determining whether a response has been timely filed. Provided a Substantive Appeal has been timely filed in accordance with paragraph (b) of this section, the response to a Supplemental Statement of the Case is optional and is not required for the perfection of an appeal.