A complete petition for remission or mitigation must be filed before the expiration of three months after the sale or other disposition of the property with respect to which the petition is filed. For purposes of this part, the term “sale or other disposition” includes acquisition of the property for official use.

(Sec. 613, 46 Stat. 756, sec. 306, 49 Stat. 880; (19 U.S.C. 1613, 40 U.S.C. 304(k)))