So by "different system prompts", you mean Microsoft injects something more akin to their own modifiers into the prompt before passing it over to OpenAI?
(The same way somebody might modify their own prompt, "explain metaphysics" with their own modifiers like "in the tone of a redneck"?)
I assumed OpenAI could slot in extra training data as a whole extra component, but that also makes sense to me... And would probably require less effort.