If software doesn't wear out, which phase is generally the longest phase in the SDLC? Maintenance begins in the first few weeks of implementation and may last for many years until such time as the system is declared obsolete. For example, changes that occur at a university often require maintenance of the system. Describe the software modifications that might be needed if the university changed all the classes offered by a particular academic department to e-learning so that no classrooms were needed. Describe the changes that might be needed to accommodate students who have more than one email address.