Amazon Autorip?

For some music purchases (vinyl or CD) Amazon offers Autorip - basically you get the music in MP3 for free as well. It used to be that they sent you a link to the files and you could download them, but for a recent vinyl purchase that supposedly came with Autorip I never received it.

Turns out the files are "added to your Amazon Music login"; I didn't know this and only discovered what Amazon Music was and set up an account a couple of days after I bought the LP.

Question is, has anyone successfully got Amazon to give them the MP3s *after* their purchase? Basically saying "I didn't have an account but I do now, please can I get them"?