Subject to valid existing rights, lands designated as wilderness by this subchapter shall be managed by the Secretary, as appropriate, in accordance with the Wilderness Act (
16 U.S.C.
1131 et seq.) and this subchapter, except that, with respect to any wilderness areas designated by this subchapter, any reference in the Wilderness Act to the effective date of the Wilderness Act shall be deemed to be a reference to October 24, 2000.