Hi Aneez,
The answer depends on the code changes introduced. If the change resulted only in rearranging UI controls, then this should not break the tests. But if the change resulted in replaced controls or modified business logic, then you will have to adjust the tests accordingly.
Just to warn you/your management against (possibly) false hopes - you must treat test automation as a 'smaller development project within the bigger one'. Your automation efforts must be correlated with the development flow and this must be done from the very start of the development. 99% that test automation will fail (or appear to be ineffective, which is, basically, the same) if you are said to test automate already existing application. You must to establish the communication process with Development so that you are warned in advance about the changes planned for the application (replacement of the used controls, databases, business logic, etc.) so that you can prepare for them and minimize the time that your tests are non-functional. It is great if you can participate in evaluation of the UI controls planned to be used in the application to check if this or that control can be automated and how many efforts are required for this.
