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Hello,This appears to be a bit of a peculiar scenario/bug related to using the "hidden" email address, but I don't have a solution and I'm hoping someone can help...Context:The user's Apple ID is a now defunct @mac.com address which, for reasons that (I imagine) are related to the @mac.com / MobileMe subscription, cannot be changedThere is a @icloud.com Primary Contact address on the accountWhen the user taps Sign in with Apple the modal is displayedThe user can select either the @mac.com or @icloud.com address in the "Share my email" optionWhen the user signs in with either "Share my email" options, the process succeeds.The user cannot select anything other the defunct @mac.com address for forwarding when selecting the "Hidden" optionWhen selecting the "Hidden" option, the sign up fails as not completed but there is no error returned to the delegateI've tested on my own in-development apps and other production apps (e.g. Kayak) and this behaviour is reproducible. So a few questions:Is it expected that Apple IDs that have unusuable (and non-editable) email addresses are not allowed to use the privacy relay option?Is it expected that Sign In Not Completed should occur without an associated error being received by the delegate?