I also received an incoming call from Apple Developer Support (512) 884-5022 on May 29 at 10:17AM Pacific Time that I managed to miss. I don't normally tether myself to my phone, but since that missed call, I have been and unfortunately, no new calls originating from them.
I immediately put in a "Get a call" from Apple Developer Support, but they were unable to give me any information, as the case has been escalated for quite some time and they don't have access to the escalation notes/work.