Why does Shantou teacher recruitment limit graduation time?

In order to alleviate the employment pressure of college students. Shantou is a city. The reason why this city restricts the graduation time for recruiting teachers is to relieve the employment pressure of college students and increase employment. Shantou, referred to as "Shantou" for short, is a prefecture-level city under the jurisdiction of Guangdong Province, one of the four cities in Chaoshan, a city in Shantou-Chaoshan metropolitan area and a special economic zone.