Whenever a merger, transfer, demerger or any other legal change is envisaged which would have the effect of calling into question an agreement or arrangement, the employers and the trade union organisations representing the employees in the undertakings or establishments concerned may negotiate and conclude an agreement or arrangement replacing the agreements and arrangements called into question and revising the agreements and arrangements applicable in the undertaking or establishment to which the employment contracts are transferred. This agreement will come into force on the date of the event that led to the dispute.