PublishPress Authors and the WordPress interface
The PublishPress Authors plugin does make some small changes to the WordPress admin interface. This is done to make the plugin easier to use and to avoid confusion.
One key change is that PublishPress Authors removes the “Author” dropdown from inside the WordPress editing screen. This dropdown is shown below, but you won’t see it with PublishPress Authors installed.
The only places to add and remove authors is this metabox, or the “Quick Edit” option.