diff --git a/setup-auto-updates.sh b/setup-auto-updates.sh
index 2ab1539..c4da51d 100644
--- a/setup-auto-updates.sh
+++ b/setup-auto-updates.sh
@@ -120,6 +120,23 @@ enable_timers_if_systemd() {
   fi
 }
 
+wait_for_apt_units() {
+  # Wait for apt-daily/apt-daily-upgrade units to finish (up to ~120s)
+  if command -v systemctl >/dev/null 2>&1; then
+    local units=(apt-daily.service apt-daily-upgrade.service)
+    for i in {1..60}; do
+      local busy=0
+      for u in "${units[@]}"; do
+        systemctl is-active --quiet "$u" && { busy=1; break; }
+      done
+      (( busy == 0 )) && return 0
+      (( i % 10 == 0 )) && echo "[INFO] apt units busy…waiting $((i*2))s"
+      sleep 2
+    done
+    echo "[WARN] apt units still busy after ~120s; continuing anyway."
+  fi
+}
+
 validate_with_dryrun() {
   wait_for_apt || true
   wait_for_apt_units || true