Section 840 - Applicability(a) Existing districts.-- Except as provided for in subsection (d), any existing business improvement district or downtown improvement district established prior to the effective date of this act shall remain in existence and shall be governed by the act of May 2, 1945 (P.L. 382, No. 164), known as the Municipality Authorities Act of 1945, insofar as it relates to business improvement districts or 53 Pa.C.S. Ch. 54 (relating to business improvement districts).(b) Districts created subsequently.--Any NID established subsequent to the effective date of this act shall be governed by the provisions of this act.(c) Previously terminated districts.--Any business improvement district or downtown improvement district in existence prior to the effective date of this act which is terminated shall, upon its reestablishment, be governed by the provisions of this act. This shall include any termination resulting from a sunset provision in any municipal agreement or ordinance.(d) Additional requirements.--Any business improvement district or downtown improvement district in existence on the effective date of this act shall: (1) be required to carry out any duty or responsibility imposed on NIDs under this act; and(2) possess any additional power given to NIDs under this act without having to restructure or reorganize under this act. 2000, Dec. 20, P.L. 949, No. 130, § 10, effective in 60 days.