(1) Contracts or leases entered into prior to January 15, 2011, with respect to any program or function transferred to the department of intellectual and developmental disabilities with any entity, corporation, agency, enterprise or person, shall continue in full force and effect as to all essential provisions in accordance with the terms and conditions of the contracts in existence on January 15, 2011, to the same extent as if such contracts had originally been entered into by and between such entity, corporation, agency, enterprise or person and the department of intellectual and developmental disabilities, unless and until such contracts or leases are amended or modified by the parties thereto or until the expiration of such contract.
(2) This part shall not be implemented in any manner which violates the prohibition against impairment of contract obligations as contained in the Constitution of Tennessee, Article I, § 20.