1. Look at the original labor contract you signed, and see whether your post or job responsibilities are agreed, whether there is an agreement or condition for changing posts, and whether the work place is agreed. If the contract stipulates that your job position is a designer and your work place is this city, the company has no right to unilaterally change the contract and ask you to be a "lecturer" in Jiangxia. If there is no agreement in the contract, the company can transfer you to "Jiangxia" as a "lecturer" according to the needs of the work.
2. Rights protection should be based on legal provisions and labor contracts. How to protect rights mainly depends on the company's illegality and breach of contract. Your statement is limited, and it is impossible to judge the right or wrong of the parties here.
3. The salary shall be paid until the date of termination of the contract. Failure to pay wages on time will constitute a crime.