Sandbox: How to restrict Test / Training Users to Only Sandbox?

We have a large QB app that will be launched soon to ~200 users.   The majority of users will be View only and casually (perhaps once per week).   Approximately 25% of the users will be key participants and will be Super Users who will be 'living' in the App.   

We set up a Sandbox for temporary use as a Testing / Training environment for these Super Users.   Going forward, we will use the Sandbox in the traditional sense of making major changes there and then publishing those changes after appropriate testing.

Question:   How do we limit Tester access to ONLY the Sandbox during the next 2 weeks for this group to complete their intensive Testing / Tire Kicking process?   We are concerned that they may accidentally create test records in the production data set, so we would like to restrict them to only the Sandbox environment for the next 2 weeks.   After the testing period, we would provide them access to the Live environment.  

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Annetta Coleman
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