5. The parties to a collective agreement contemplated in section 2 may negotiate and approve clauses at a local or regional level.
The matters dealt with in those negotiations and the framework within which they are conducted are provided for in the clauses negotiated and approved at the national level between two hundred and seventy days and one hundred and eighty days before the date of expiration of the collective agreement. The matters that have not so been defined at the expiry of that period are the subject of clauses negotiated and approved at the national level, unless otherwise decided by the Government.