49 CFR §29.306

1. (a)The duration of a funding agreement is one year unless the Department and a Tribe negotiate a multi-year funding agreement or, for an initial funding agreement, a partial-year agreement.
2. (b)Each funding agreement will remain in full force and effect until the Department and the Tribe execute a subsequent funding agreement, except when:
   1. (1)The Tribe provides notice to the Department that it is withdrawing or retroceding funds for the operation of one or more PSFAs (or portions thereof) identified in the funding agreement;
   2. (2)The Department terminates the funding agreement under 23 U.S.C. 207(f)(2); or
   3. (3)The Department and the Tribe agree otherwise.