(a)any of the conditions of the Non-Scheduled Operator's Permit has not been complied with and the failure is due to any wilful act or default on the part of the holder of such Non-Scheduled Operator's Permit or by any of his servants or agents, irrespective of whether or not such wilful act or default of the servant or agent was with the knowledge or approval of the holder of the Non-Scheduled Operator's Permit, or