do regular update checks

src/main.cpp

@@ -385,6 +385,8 @@ void ICACHE_FLASH_ATTR sendValues() {
   if (loop_count == 1) {
     XD0OTA ota;
     ota.update();
+  } else if (loop_count > 720) { // do an update every 12h
+    loop_count = 0;
   }
   loop_count++;