A project can be replaced by another project by clicking on the button, which appears on mouse-over to the left of the project name in the List of Projects and selecting "Replace".
Replace options
The following options can be set in the replace dialog:
Project that replaces the current project: A project from the List of Projects that replaces the current project
Save replaced project as: A new project name to save the current project
Here,
"TIS Manual Demo Project" is moved to "TIS Manual Demo Project Backup" and
"Confluence Manual" is moved to "TIS Manual Demo Project".