Dear Athiya san,
Kindly refer to my reply below,
From above detail, ELNA inform in report to METCO was production date : 3-Jul-15, But as below detail inform effective date was Jun-15. Which it was action before production date.
Based on the report it is mention that this foreign material is not belong to Elna PCB product. Hence this foreign material is came from punching part number (Metco part is routing part). This improvement shows that Elna is preventing other PCB dust from adhering at the PCB board before send to METCO.