I wouldn't freak out too much. The white interiors RWD have to be made from the factory. Plenty of folks ordered, and only 1 or 2 got rejected, for unknown reasons. People who were pending LR RWD orders when white interior became an option were able to switch to it. I can't imagine they'd do that if they weren't going to make them, or Tesla wouldn't take the extra money for the interior. I don't think you (or I) have anything to worry about, we just won't take delivery until December, when the white MRs take delivery.
I just got off the phone with someone at Tesla. He double checked with his supervisor while he put me on hold, and it seems the supervisor was aware that prior to the MR annoucement, there was no white interior on the LR RWD, but that upon ordering "off menu" that people asked for this configuration. He said what I'm configured is what I'm going to get, and that they would have reached out to me by now if they couldn't make the particular car.
I'm gonna let it all play out until at least the middle of December (since I'm in So Cal) before I start weighing options. I can always head up to Fremont and take delivery of a vehicle, as I'm planning to be in San Francisco the weekend of the 22nd anyway. I kind of like that others are canceling their white interior orders, that means mine will be more unique, I'll be glad I stayed disciplined and didn't poop my pants and settle, and hopefully I get mine faster than I would have originally before others switched.
P.S. My friend's account finally updated with the referral credit, for what that's worth.