Notwithstanding the coming into force of the amendments to the definition of worker in section 279 of the Trade Union and Labour Relations (Consolidation) Act 199294 (health service practitioners) made by paragraph 7 of the Schedule to the Primary Medical Services (Scotland) Act 2004 (Consequential Modifications) Order 2004, in relation to any complaint arising in respect of a matter which occurred before 1st April 2004, section 279 shall have effect as if those amendments had not been brought into force.