You have tested the application and it is released. The user asks for some changes in the project and gives one week time to complete it. Out of the one week, 6 days is taken by the developer to make the changes. So you have only one day to test it. What will you do in the case in case of manual testing?
In this situation i will prefer to consult the client and request him to extend the date of release for another 1 week,for thorough testing and fix the defects that are found,so that the quality product can be released.
Because it took 6 days to complete the coding part.Only 1 day for testing is remaining.Why are we testing?to find the hidden defects.So if you start testing the major functionalities in that single day left,found any defects.Than what is the situation?We cannot release the product,because there are defects in the major functionalities.So extending the date is the best possible way in this situation.Releasing a quality product is also as important as releasing the product on time.Client will be happy if there are no serious issues with the product,though you have took extra 1 week to release the product.