4. The Digital Services Coordinator of establishment shall take utmost account of the request pursuant to paragraphs 1 or 2 of this Article. Where it considers that it has insufficient information to act upon the request and has reasons to consider that the Digital Services Coordinator that sent the request, or the Board, could provide additional information, the Digital Services Coordinator of establishment may either request such information in accordance with Article 57 or, alternatively, may launch a joint investigation pursuant to Article 60(1) involving at least the requesting Digital Services Coordinator. The period laid down in paragraph 5 of this Article shall be suspended until that additional information is provided or until the invitation to participate in the joint investigation is refused.