diff --git a/rsync-backup/metadata.yml b/rsync-backup/metadata.yml
index 4afd39e8..568257e1 100644
--- a/rsync-backup/metadata.yml
+++ b/rsync-backup/metadata.yml
@@ -13,5 +13,5 @@ uses:
     default-options:
       ## backup every day on random time
       schedule: !bash-stdout |
-        printf "%d %d * * *" "$((RANDOM % 60))" "$((RANDOM % 6))"
+        printf "%d %s * * *" "$((RANDOM % 60))" "$((RANDOM % 6))-23/6"