A quick update regarding my T-Mobile woes: they reset my password, which caused me to go through the new account creation process. However, this “new” account retained my purchase history from before and all seems right in the world again.
Now I have all of the options I researched available to me. I asked on Twitter whether T-Mobile or Verizon fares better in the Moscone area of San Francisco, but I got no particularly definitive feedback. Seems like I’ll be carrying two SIMs with me on Monday and playing it by ear.
Unlike my password validation issue, this is the kind of problem I don’t really mind having.