@Dylan Taylor Thanks for posting in our Q&A.
Honestly, a test environment isn’t actually necessary. If you just buy a few seats of O365 Mobility + Security, or M365 E3 then you’ve got what you need. If you want an actual test bed, just sign up for a 30-day Trial.
https://learn.microsoft.com/en-us/mem/intune/fundamentals/free-trial-sign-up
But consider that if you just build the policies in production and scope them to a few test users/devices, you’ll be doing the same thing. This method has always worked well, and the other benefit is no re-building, just change the scope of who it applies to once everything goes right.
Hope it will clarify something.
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