How did Shenzhen Flextronics know that it had turned positive?

The probation period expires. According to the provisions of the Labor Law, continuing employment after the probation period is regarded as becoming a full member. Therefore, Shenzhen Flextronics is regarded as automatically becoming a full member after the probation period expires. Flextronics Industrial (Shenzhen) Co., Ltd. (formerly known as Shenzhen CommScope Electronic Technology Co., Ltd.) was established in 1994, located in Shenzhen, Guangdong Province.