By default, the main view of a publication that will be published to the public network is based on the original author. This means that any user that opens that document in the public context, will see the main view based on the original author no matter how many changes or other authors contributed to it.
Inside a group, the main view is based on all the changes from all the editors of a group. That means that if I open a group in the group context, I will see the latest version based on all the editors of that group.