Hi @NigelW61 · Thank you for reaching out.
Azure AD B2C supports maximum of 200 files to be uploaded to the Identity Experience Framework blade. So, you can have two separate sets of Base/Extension/RP files with same content but with different policy names - One for production and other for testing/dev purpose. You can use naming convention like TrustFrameworkBase-Prod and TrustFrameworkBase-Dev, for example.
Always perform testing on the test/dev policies and once you are done with the testing and confirmed that the changes are not causing any issues, you can modify the production policies accordingly and then upload & override the files for production usage.
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