diff --git a/roles/backup_client/templates/duply_main_conf.j2 b/roles/backup_client/templates/duply_main_conf.j2
index 97260ddebc19cebc506a5908f2c2ee6f3e123a7a..e19ec72df902180e3db2f79d616b59797e51a83c 100644
--- a/roles/backup_client/templates/duply_main_conf.j2
+++ b/roles/backup_client/templates/duply_main_conf.j2
@@ -14,7 +14,7 @@ GPG_OPTS="--homedir /etc/duply/main/gnupg/ --trust-model always"
 # DUPL_PARAMS and --ssh-options):
 #
 #   - Pass in custom options for user/global known_hosts files (not
-#     possible with Duplicity shipping with Debian 10 Buster).
+#     possible with Duplicity shipping with Debian 11 Bullseye).
 #   - Reduce logging verbosity (avoiding output from sftp that mentions
 #     updates of user's known_hosts file with IP addresses).
 TARGET='pexpect+sftp://{{ backup_client_username }}@{{ backup_server }}:{{ backup_server_port }}/{{ backup_server_destination }}'