Safari autofill using out-of-date contact information

In AutoFill, I have "using information from my contacts", "credit cards", and "other forms" selected. I do not have "use names and passwords" selected; I use 1Password as my password manager and fill in usernames and passwords from there. However, it is the Safari (not 1Password) autofill that is using my old email address. I cannot find the old email stored anywhere.

Is there a .plist file somewhere that might have the old information stored? Do I recall that in ancient versions of Safari you specified the autofill values directly in Safari preferences rather than in the contact card? Maybe there is some old setting like that that is no longer accessed in the Safari interface?

I am currently running macOS 13.2, Safari 16.3, iOS 16.2. Looks like it was in 2018 that my old email went completely defunct, but I stopped using it a year or two before then. It was my primary email from 2004 until I received warnings that it would be going away in 2016 or 2017; I was using Macs and Safari throughout that period, so a wide range of versions, updates, and computer and phone replacements, so there may be preferences that have propagated forward from as long ago as 2004. The old mailing address I see routinely was my primary address form 2017 to 2020. Older mailing address (pre-2017) do not autofill.

This email (and old mailing address) appears whenever I have a form that requests an email or address that is not a login page (eg checkout at an online retailer). I see no particular pattern, and it is not specific to any web site that I can identify. I just tried checking out as a guest at bestbuy.com, and on both my iPhone and my Mac it correctly gave my two current emails (home and work) from my contact card, plus the iCloud hide my email option, as the choices for autofill in the email field. At other times, it only gives my defunct email as an option.