Bypass Subscription When In TestFlight

We are hoping to do a first release on app store with our subscription paywall, however, we want to allow our testflight users to continue to test for free. I want to check if app is downloaded via testflight environment and conditionally bypass the paywall. 

StoreKit has a Method called a thing called AppTransaction that has a environment field to it. There are StackOverflow post that resolved it using swift, but i am using expo. Is there something equivalent in revenueCat? What is the best way to approach this?