Sim, você pode "conectar", mas será necessário alterar sua senha, pelo menos nas distribuições do Ubuntu. Alguns servidores se comportarão de maneira diferente.
debug1: Authentications that can continue: publickey,password
debug3: start over, passed a different list publickey,password
debug3: preferred gssapi-keyex,gssapi-with-mic,gssapi,publickey,keyboard-interactive,password
debug3: authmethod_lookup publickey
debug3: remaining preferred: keyboard-interactive,password
debug3: authmethod_is_enabled publickey
debug1: Next authentication method: publickey
debug1: Trying private key: /home/testsftpuser/.ssh/id_rsa
debug1: read PEM private key done: type RSA
debug3: sign_and_send_pubkey
debug2: we sent a publickey packet, wait for reply
debug3: Wrote 656 bytes for a total of 1799
debug1: Authentication succeeded (publickey).
debug1: channel 0: new [client-session]
debug3: ssh_session2_open: channel_new: 0
debug2: channel 0: send open
Nenhum acesso será concedido até que sua senha seja alterada:
You are required to change your password immediately (password aged)
Linux devftp01 2.6.66-38-server #43-Ubuntu SMP Thu Sep 16 16:05:42 UTC 2010 x86_64 GNU/Linux
Ubuntu 12.04.4 LTS
WARNING: Your password has expired.
You must change your password now and login again!
Changing password for testsftpuser.
(current) UNIX password: