The order of the projects is determined by the date they are created, showing them from newest (top left) to the oldest (bottom right). We use the project date to arrange the projects. The date can be set via the project settings.
Changing Project Date
While in the page overview screen, click the Project Settings link, on the left side, under the publication thumbnail. In the Basic Information tab, in the right section, you will see a field called Date Project.
By default, this will state the date when you created this publication. So if you created a publication most recently, it will appear as the first project in the top left of the project overview, whereas the one you created last, will appear on the bottom right.