The Original Assured shall not be prejudiced by delay in opening up packages and/or examination of goods up to a maximum of 90 days after delivery. It is agreed that any loss or damage discovered on opening containers and/or cases and/or packages shall be deemed to have occurred during the transit insured hereunder (and irrespective of attachment of Original Assured’s interest) and shall be paid for accordingly unless proof conclusive to the contrary be established, it being understood that any containers and/or cases and/or packages showing external signs of damage are to be opened promptly.