Our application, Yunlen, was unexpectedly rejected after a minor UI update, despite having been live on the App Store for nearly a year. The rejection cites "Crypto related content," an issue we have repeatedly clarified with the Apple Review Team; frustratingly, we have been forced to provide the same detailed explanation three separate times in the same review thread, indicating our responses are being ignored and resulting in a protracted and frustrating 10-day delay to a simple update.
Guideline 2.1 violation
In such a case (former rejection) it is wise to add the explanation in the message to reviewer in submission form. That helps a new reviewer to be fully aware of the context.