I just posted a PowerShell script shared by Chris Boyd from the Project Product Group that allows you to create new accounts to connect from Project Pro for Office 365 or Project Professional to Project Online or Project Server. This, in combination with Group Policy could be used to set accounts for many users in a controlled manner. See http://blogs.msdn.com/b/brismith/archive/2015/10/19/project-server-and-project-online-creating-a-project-pro-account-using-powershell.aspx for my article and http://blogs.technet.com/b/heyscriptingguy/archive/2010/08/14/weekend-scripter-using-group-policy-to-deploy-a-windows-powershell-logon-script.aspx for an example of how Group Policy could be used.
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