As expected, nothing has come of the report.

Thank you for your engagement @DTS Engineer FB21100266 is the Feedback Assistant number - I haven't had any other "bug number" given back to me, if this is different? I had an initial response to clarify the evidence I'd submitted, then nothing further. I'm really looking for: a) confirmation if this is a bug in iOS, so that I can pass this information to management b) any suggestions of a workaround while this is fixed, given the massive impact this has had on our Apple customers for the last 2 months.

Thanks @DTS Engineer - I appreciate your help. It's interesting that your guide says "DevForums is not an official support channel", and yet when I tried to engage with Developer Code-Level Support they pushed me to DevForums implying that it is an official support channel. Do you have any way of feeding back to Code-Level Support that they shouldn't be pushing people here for official support? It sounds like all hope is lost on this issue. I guess the only workaround I can offer to affected customers is to use an Android device instead?