谢谢您的询问。您的老板在没有进行合理的performance management 之前是不能单方面决定降您的工资。在新西兰employer必须act reasonably, and in good faith.
您没有签第二份合同是对的,您在试用期内被解雇不是说employer有全权来决定:
While an employer is not required to provide written reasons for an employee’s dismissal, there is an expectation that an employer, acting in good faith, would inform the employee as to why he or she has been dismissed. Any provisions about giving notice in the employment agreement will need to be adhered to.