No, I had unused Sturdy Steel Keys even last year. They had not been transformed with the Update 37, just removed from the store, and the chests from Lalia's Market, too. The transformation might have happened in the meantime. If it did, it was not too long ago.
Edit: No, it did not happen. I just found a character which still has them, because on level 14 you can not use them.
Greetings, Polymachos
