IANAL, but far as I understand, estoppel is purely a defense when being sued by whomever made the promise. So it helps if MS sues you when you distribute copi

IANAL, but far as I understand, estoppel is purely a defense when being sued by whomever made the promise. So it helps if MS sues you when you distribute copilot-generated code that infringes on MS copyrights, but if a third party sues you, you can't claim estoppel to compel MS to help you. You would need a contractual guarantee.