Hi Declan Elkerton
Thanks for reaching out to Microsoft Q&A.
According the official documentation here- https://learn.microsoft.com/en-us/azure/logic-apps/add-run-csharp-scripts, this feature is still in preview. This means that even if feature is not listed as "preview" for inline code, it is not generally available officially and still in transition phase where feature is near to General Availability.
It is safest to treat this as preview only until the official documentation for its GA comes in.
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