The earliest address that I used publicly and I still have access to is from September 01, 2015:
-----BEGIN BITCOIN SIGNED MESSAGE-----
nomadcrypto from bitcointalk.
date: May 21 2019
address: 1KJcGmkP4HCzJQ9nPW9J1qaAnGkkSr6tyK
-----BEGIN SIGNATURE-----
H0/HiI6U7d8JB95LZ1nCIhngB2KSCE4xnpRKSXrPQncTZtn6gDtJ8kvdD6BVEz9KLyJBkFe46EJMXTkz2Alj8R4=
-----END BITCOIN SIGNED MESSAGE-----
Can someone please verify and quote?