I'm coding resumable uploads using iOS 17's URLSession's uploadTask(withResumeData:. This function returns a non-Optional URLSessionUploadTask and does not throw. In cases where the system determines the resumeData is no longer valid, how do I detect that (so I can create a new URLSessionUploadTask from scratch)? I'm doing this for background uploads, so it's all URLSessionDelegate apis, but what are the failure modes, and what Error types and Codes would we get specially? Obviously, I expect the resume data is no longer usable or necessary when get a server success i.e. in the 2xx range. Does the resume data also become invalid for other server responses, like 4xx's? or 5xx's?. I expect the resume data usually shouldn't become invalid when getting URLError's like .networkConnectionLost, since that's like half the point of having the feature in the first place, to resume after the a broken network connection. But I do expect that if the resumeData is invalid, then I should be able to reach the server and get a server response, so in that case what Code would we get? I'm assuming the system is caching our upload file somewhere, and the resume data somehow makes a reference to it, so does that file get optimized away at some point in time when left untouched, and need us to start a fresh upload? We are also saving the file for potential future re-uploads, until we get certain assurances of completion from our backend, but I am just wondering on which logic branches I need to determine that the resumeData I thought I could use is no longer usable.