diff --git a/examples/simple_repeater/MyMesh.cpp b/examples/simple_repeater/MyMesh.cpp
index a711ec0a51..ef86df5952 100644
--- a/examples/simple_repeater/MyMesh.cpp
+++ b/examples/simple_repeater/MyMesh.cpp
@@ -29,6 +29,16 @@
   #define ADVERT_LON 0.0
 #endif
 
+// GPS defaults for a NEW install. Boards with a permanently-fitted GNSS (and no
+// UI to switch it on) override these in their platformio.ini; every other board
+// keeps the historical "GPS off, advertise the configured coordinates" defaults.
+#ifndef GPS_ENABLED_DEFAULT
+  #define GPS_ENABLED_DEFAULT 0
+#endif
+#ifndef ADVERT_LOC_POLICY_DEFAULT
+  #define ADVERT_LOC_POLICY_DEFAULT ADVERT_LOC_PREFS
+#endif
+
 #ifndef ADMIN_PASSWORD
   #define ADMIN_PASSWORD "password"
 #endif
@@ -919,9 +929,9 @@ MyMesh::MyMesh(mesh::MainBoard &board, mesh::Radio &radio, mesh::MillisecondCloc
   StrHelper::strncpy(_prefs.bridge_secret, "LVSITANOS", sizeof(_prefs.bridge_secret));
 
   // GPS defaults
-  _prefs.gps_enabled = 0;
+  _prefs.gps_enabled = GPS_ENABLED_DEFAULT;
   _prefs.gps_interval = 0;
-  _prefs.advert_loc_policy = ADVERT_LOC_PREFS;
+  _prefs.advert_loc_policy = ADVERT_LOC_POLICY_DEFAULT;
 
   _prefs.adc_multiplier = 0.0f; // 0.0f means use default board multiplier
 
diff --git a/examples/simple_room_server/MyMesh.cpp b/examples/simple_room_server/MyMesh.cpp
index 546d094fc8..fb66008f08 100644
--- a/examples/simple_room_server/MyMesh.cpp
+++ b/examples/simple_room_server/MyMesh.cpp
@@ -670,9 +670,9 @@ MyMesh::MyMesh(mesh::MainBoard &board, mesh::Radio &radio, mesh::MillisecondCloc
 #endif
 
   // GPS defaults
-  _prefs.gps_enabled = 0;
+  _prefs.gps_enabled = GPS_ENABLED_DEFAULT;
   _prefs.gps_interval = 0;
-  _prefs.advert_loc_policy = ADVERT_LOC_PREFS;
+  _prefs.advert_loc_policy = ADVERT_LOC_POLICY_DEFAULT;
 
 #if defined(USE_SX1262) || defined(USE_SX1268)
 #ifdef SX126X_RX_BOOSTED_GAIN
diff --git a/examples/simple_room_server/MyMesh.h b/examples/simple_room_server/MyMesh.h
index 5cf949c6bd..d376ee958e 100644
--- a/examples/simple_room_server/MyMesh.h
+++ b/examples/simple_room_server/MyMesh.h
@@ -61,6 +61,16 @@
   #define  ADVERT_LON  0.0
 #endif
 
+// GPS defaults for a NEW install. Boards with a permanently-fitted GNSS (and no
+// UI to switch it on) override these in their platformio.ini; every other board
+// keeps the historical "GPS off, advertise the configured coordinates" defaults.
+#ifndef GPS_ENABLED_DEFAULT
+  #define  GPS_ENABLED_DEFAULT  0
+#endif
+#ifndef ADVERT_LOC_POLICY_DEFAULT
+  #define  ADVERT_LOC_POLICY_DEFAULT  ADVERT_LOC_PREFS
+#endif
+
 #ifndef ADMIN_PASSWORD
   #define  ADMIN_PASSWORD  "password"
 #endif
diff --git a/variants/thinknode_m6/platformio.ini b/variants/thinknode_m6/platformio.ini
index ad7e6902cf..cfac5e2cd5 100644
--- a/variants/thinknode_m6/platformio.ini
+++ b/variants/thinknode_m6/platformio.ini
@@ -47,6 +47,16 @@ build_flags =
   -D ADVERT_LON=0.0
   -D ADMIN_PASSWORD='"password"'
   -D MAX_NEIGHBOURS=50
+; The L76K GNSS is soldered to the M6 and the enclosure is sealed, so there is
+; no button or screen to switch GPS on with. Skip the 1s "is a GPS attached?"
+; probe (it gates the 'gps' setting, and losing that race leaves GPS
+; unreachable until reboot), enable GPS for new installs, and advertise the
+; position the GNSS actually reports instead of the fixed 0,0 above.
+; All of it stays changeable at runtime over the serial CLI: 'gps on'/'gps off',
+; 'gps advert prefs|share|none', and bare 'gps' to print fix + satellite count.
+  -D ENV_SKIP_GPS_DETECT=1
+  -D GPS_ENABLED_DEFAULT=1
+  -D ADVERT_LOC_POLICY_DEFAULT=ADVERT_LOC_SHARE
 ;  -D MESH_PACKET_LOGGING=1
 ;  -D MESH_DEBUG=1
 ;  -D GPS_NMEA_DEBUG=1
@@ -64,6 +74,13 @@ build_flags =
   -D ADVERT_LON=0.0
   -D ADMIN_PASSWORD='"password"'
   -D ROOM_PASSWORD='"hello"'
+; Same reasoning as the repeater env above: the L76K is soldered on and the
+; enclosure is sealed, so GPS has to come up enabled and advertise the position
+; the GNSS actually reports. Runtime CLI still wins ('gps on'/'gps off',
+; 'gps advert prefs|share|none').
+  -D ENV_SKIP_GPS_DETECT=1
+  -D GPS_ENABLED_DEFAULT=1
+  -D ADVERT_LOC_POLICY_DEFAULT=ADVERT_LOC_SHARE
 ;  -D MESH_PACKET_LOGGING=1
 ;  -D MESH_DEBUG=1
 build_src_filter = ${ThinkNode_M6.build_src_filter}