Here’s how to get the new Teams client for your organization if you are a Teams Administrator.
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Get the New Teams client for your organization | Teams Admin Center
Here’s how you can enable Users to choose to update to the new Teams if you are a Teams Administrator in M365 Admin Center So since you are using the current (or old) Teams version,and the option to enable New Teams is not avilable to you, you would see no option to update in this Title Bar of the Teams app itself.
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