We don't want for the users to have to regenerate their email address auto complete entries once again. Next week I will be switching them over to using Office 365 and will be creating new Mac Outlook 2016 profiles for each and every user that will be communicating with the Office 365 server instead of with the Gmail servers. These auto complete entries are important since when the users type the first few characters of someone's email address or name the correct email address will appear as an auto complete entry within Outlook (see the screenshot). All users currently have thousands of email auto complete entries within their Outlook profiles.
A company I am working for is currently using Mac Outlook 2016 to send and receive emails through their Gmail email service.