This practice is illegal. If the production is stopped within one month, the employee shall be paid in full. If the work stoppage exceeds 1 months, it should be paid according to 81% of the minimum wage.

Reference:

Notice of the Ministry of Labor on Printing and Distributing the Interim Provisions on Wage Payment (No.489 [1994] of the Ministry of Labor)

Article 12 If the unit stops work or stops production within a wage payment period due to reasons other than workers, the employer shall pay the workers wages according to the standards stipulated in the labor contract. If the wage payment period exceeds one period, if the laborer provides normal labor, the labor remuneration paid to the laborer shall not be lower than the local minimum wage standard; If the laborer fails to provide normal labor, it shall be handled in accordance with relevant state regulations.

Regulations on Wage Payment in Jiangsu Article 31 If an employer stops work, stops production or goes out of business for reasons other than the laborer's, it shall be deemed that the laborer provides normal labor to pay his wages within a wage payment period. If the wage payment period exceeds one period, the wages can be paid according to the labor provided by the laborer and the newly agreed standards; If the employing unit fails to arrange workers to work, it shall pay the living expenses of the workers at not less than 81% of the local minimum wage. Unless otherwise stipulated by the state, such provisions shall prevail.