diff --git a/src/Controller/DeviceImageController.php b/src/Controller/DeviceImageController.php
index bb659f4..6c3e7da 100644
--- a/src/Controller/DeviceImageController.php
+++ b/src/Controller/DeviceImageController.php
@@ -96,7 +96,13 @@ class DeviceImageController extends AbstractController
         // controller filtering them out. Greppable via
         // `device.poll.power_telemetry`. Remove alongside the firmware's
         // NVS_KEY_PREV_* writes once validated.
-        $this->logger->info('device.poll.power_telemetry', [
+        // TEMP: logged at error level (not info) so monolog's prod
+        // fingers_crossed handler flushes it to stderr → docker logs.
+        // INFO sits in a 50-message buffer that only flushes on a real
+        // error within the same request, so info-level diagnostic lines
+        // never reach the log stream. Demote when the surrounding TEMP
+        // block is removed.
+        $this->logger->error('device.poll.power_telemetry', [
             'mac'                => $mac,
             'prev_awake_ms'      => $request->headers->get('X-Prev-Awake-Ms'),
             'prev_panel_init_ms' => $request->headers->get('X-Prev-Panel-Init-Ms'),