On and after October 12, 1984, such appropriations [appropriations for the Bureau of Indian Affairs (except the revolving fund for loans and the Indian loan guarantee and insurance fund)] under this or any other act shall be available for: the expenses of exhibits; advance payments for services (including services which may extend beyond the current fiscal year) under contracts executed pursuant to the Act of June 4, 1936 (
48 Stat. 596), as amended (
25 U.S.C.
452 et seq.), the Act of August 3, 1956 (
70 Stat. 896), as amended (
25 U.S.C.
309 et seq.), and legislation terminating Federal supervision over certain tribes; and expenses required by continuing or permanent treaty provision.