How to change finished goods automatically to hold status after 180 days from production date?

In Automotive Dept,  we would like to see the finished goods in Hold status after 180 days from production date. According to this reason we have make a trial on a list of product. We have changed shelf life as 180 days. But it did not work. What should we do to automatically drop finished goods to Hold status after 180 days from production date?