Ran into something very non-obvious about how the stimulus payments are handled:
If you got a tax refund using direct-deposit in 2018 or 2019, you don't need to do anything, your $1200 will direct-deposit to the same account.
But if you paid using direct-withdrawal in those years, the IRS can't/won't direct-deposit to that account automatically. You need to go online and give them routing/account numbers again. Yes, they're the same routing/account numbers for deposit and withdrawal and no, I have no idea why they can't put money into an account they just took money out of two months ago.
(FYI, the identifying information used to get that far has to match your 1040 exactly. E.g. spelling out "Drive" instead of "Dr." will throw an error. And three errors will lock you out for 24 hours. DAMHIKT)