So, interesting development today. After seeing others in MN getting end of September dates after their initial delay call, I called Delivery Scheduling one more time to politely inquire if I can get any date sooner than October 1 or onward (very busy week/month for me). They told me that they could not because "all slots before that were full". I thanked them and asked if there was any way to be notified if another opening came up sooner. He indicated that only my IDA can proactively look for openings like that. After I mentioned that my initial IDA had been very unresponsive, I asked who they see as my IDA, only to receive a name totally different than the IDA who contacted me initially to confirm my appointment (and different than the DSA that originally emailed me to schedule, also non-responsive). I asked him if he could have this new IDA contact me.
That person then contacted me a couple of hours later and was WORLDS APART from other reps I've been working with. He was very kind, courteous, texted me afterwards, told me to call anytime, seemed very excited for me, thanked me repeatedly for being one of the people that is making it possible for Tesla to do something historic, and sounded like he genuinely wanted to help. He was able to move me to 9/28 and thought it was strange that the system initially told him all slots were full when he could see that they clearly weren't from some other view he had.
What I thought was interesting, is he mentioned that he had been pulled from another department to help with this, so Tesla is clearly going all out to correct for their delivery issues (something he acknowledged on his own accord).
While he couldn't tell me exactly where my vehicle was, he could confirm that even though my VIN disappeared from the website, it is indeed still assigned to me and it will reappear precisely 7 days prior to my newly scheduled date. He also confirmed that I should see the ACH payment option open 48 hours prior to delivery.