Outlook not auto updating
To disable Office 2016 auto updates, there is a slight difference in Windows 10 and Windows 8/7. (Right click on Windows 10 desktop and from the context menu select Display Settings.
Microsoft Outlook connects to the local Exchange autodiscover service, which in turn redirects Outlook to Office 365, because the mailbox has been moved there.Here is the autodiscover design article which talks about the max 10 responses, and here is an article which talks about configuring a site to use specific CAS, using autodiscoversitescope feature.You haven't deployed a hybrid solution, and have created mailboxes in Office 365 with a different SMTP domain name to on-premises Exchange.When the PC is on your network, it will still try and resolve the end point using SCP.As a test on the user’s PC, you want to disable SCP lookup and force the user’s PC to only use the DNS record for autodisover. Please note: this information was accurate at the time of writing this article (30 April 2015).