diff --git a/examples/companion_radio/MyMesh.cpp b/examples/companion_radio/MyMesh.cpp
index 4388fd1..f2a91ed 100644
--- a/examples/companion_radio/MyMesh.cpp
+++ b/examples/companion_radio/MyMesh.cpp
@@ -1193,12 +1193,24 @@ void MyMesh::begin(bool has_display) {
       _prefs.gps_baudrate != 9600 && _prefs.gps_baudrate != 19200 &&
       _prefs.gps_baudrate != 38400 && _prefs.gps_baudrate != 57600 &&
       _prefs.gps_baudrate != 115200) {
+    Serial.printf("PREFS: invalid gps_baudrate=%lu — reset to 0 (default)\n",
+                  (unsigned long)_prefs.gps_baudrate);
     _prefs.gps_baudrate = 0;  // reset to default if invalid
   }
-  // interference_threshold: 0 = disabled, minimum functional value is 14
+  // interference_threshold: 0 = disabled, minimum functional value is 14, max sane ~30
   if (_prefs.interference_threshold > 0 && _prefs.interference_threshold < 14) {
     _prefs.interference_threshold = 0;
   }
+  if (_prefs.interference_threshold > 50) {
+    Serial.printf("PREFS: invalid interference_threshold=%d — reset to 0 (disabled)\n",
+                  _prefs.interference_threshold);
+    _prefs.interference_threshold = 0;  // garbage from prefs upgrade — disable
+  }
+  // Clamp remaining v1.0 fields that may contain garbage after upgrade from older firmware
+  if (_prefs.path_hash_mode > 2) _prefs.path_hash_mode = 0;
+  if (_prefs.autoadd_max_hops > 64) _prefs.autoadd_max_hops = 0;
+  if (_prefs.dark_mode > 1) _prefs.dark_mode = 0;
+  if (_prefs.portrait_mode > 1) _prefs.portrait_mode = 0;
 
 #ifdef BLE_PIN_CODE // 123456 by default
   if (_prefs.ble_pin == 0) {
diff --git a/examples/companion_radio/MyMesh.h b/examples/companion_radio/MyMesh.h
index 9b0c65e..eb593b3 100644
--- a/examples/companion_radio/MyMesh.h
+++ b/examples/companion_radio/MyMesh.h
@@ -8,11 +8,11 @@
 #define FIRMWARE_VER_CODE 10
 
 #ifndef FIRMWARE_BUILD_DATE
-#define FIRMWARE_BUILD_DATE "14 March 2026"
+#define FIRMWARE_BUILD_DATE "15 March 2026"
 #endif
 
 #ifndef FIRMWARE_VERSION
-#define FIRMWARE_VERSION "Meck v1.0"
+#define FIRMWARE_VERSION "Meck v1.0.1"
 #endif
 
 #if defined(NRF52_PLATFORM) || defined(STM32_PLATFORM)
diff --git a/examples/companion_radio/main.cpp b/examples/companion_radio/main.cpp
index ab71db5..446839b 100644
--- a/examples/companion_radio/main.cpp
+++ b/examples/companion_radio/main.cpp
@@ -1164,15 +1164,18 @@ void setup() {
   sensors.begin();
   MESH_DEBUG_PRINTLN("setup() - sensors.begin() done");
 
-  // IMPORTANT: sensors.begin() calls initBasicGPS() which steals the GPS pins for Serial1
-  // We need to reinitialize Serial2 to reclaim them
+  // IMPORTANT: sensors.begin() calls initBasicGPS() which steals the GPS pins for Serial1.
+  // We must end Serial1 first, then reclaim the pins for Serial2 (which feeds gpsStream).
   #if HAS_GPS
-    Serial2.end();  // Close any existing Serial2
+    Serial1.end();   // Release GPS pins from Serial1's UART + ISR
+    Serial2.end();   // Close any existing Serial2
     {
       uint32_t gps_baud = the_mesh.getNodePrefs()->gps_baudrate;
+      Serial.printf("GPS: prefs gps_baudrate=%lu (0=use default)\n", (unsigned long)gps_baud);
       if (gps_baud == 0) gps_baud = GPS_BAUDRATE;
       Serial2.begin(gps_baud, SERIAL_8N1, GPS_RX_PIN, GPS_TX_PIN);
-      MESH_DEBUG_PRINTLN("setup() - Reinitialized Serial2 for GPS at %lu baud", (unsigned long)gps_baud);
+      Serial.printf("GPS: Serial2 started at %lu baud (RX=%d TX=%d)\n",
+                     (unsigned long)gps_baud, GPS_RX_PIN, GPS_TX_PIN);
     }
   #endif
 
@@ -1373,10 +1376,12 @@ void setup() {
   }
   #endif
 
-  // GPS power — honour saved pref, default to enabled on first boot
+  // GPS power — honour saved pref, default to enabled on first boot.
+  // GPS is critical for timesync on standalone variants without 4G.
   #if HAS_GPS
   {
     bool gps_wanted = the_mesh.getNodePrefs()->gps_enabled;
+    Serial.printf("GPS: pref gps_enabled=%d\n", (int)gps_wanted);
     if (gps_wanted) {
       #ifdef PIN_GPS_EN
         digitalWrite(PIN_GPS_EN, GPS_EN_ACTIVE);
@@ -1388,7 +1393,7 @@ void setup() {
       #endif
       sensors.setSettingValue("gps", "0");
     }
-    MESH_DEBUG_PRINTLN("setup() - GPS power %s", gps_wanted ? "on" : "off");
+    Serial.printf("GPS: power %s, PIN_GPS_EN=%d\n", gps_wanted ? "ON" : "OFF", PIN_GPS_EN);
   }
   #endif
 
@@ -1410,6 +1415,21 @@ void loop() {
 
   sensors.loop();
 
+  // GPS diagnostic — print sentence count every 30s so we can tell if Serial2 is receiving data
+  #if HAS_GPS
+  {
+    static unsigned long lastGpsDiag = 0;
+    if (millis() - lastGpsDiag >= 30000) {
+      lastGpsDiag = millis();
+      uint32_t sentences = gpsStream.getSentenceCount();
+      uint16_t perSec = gpsStream.getSentencesPerSec();
+      Serial.printf("GPS diag: %lu sentences total, %u/sec, Serial2.available=%d, lat=%.6f lon=%.6f\n",
+                    (unsigned long)sentences, perSec, Serial2.available(),
+                    sensors.node_lat, sensors.node_lon);
+    }
+  }
+  #endif
+
   // Map screen: periodically update own GPS position and contact markers
   #if HAS_GPS
   if (ui_task.isOnMapScreen()) {