diff --git a/proto b/proto
index fc79db459..ab281311c 160000
--- a/proto
+++ b/proto
@@ -1 +1 @@
-Subproject commit fc79db45944959ee3246f6f808db18e4debab72b
+Subproject commit ab281311c49f2a9099d66fc6d211dca96d9603b3
diff --git a/src/mesh/NodeDB.cpp b/src/mesh/NodeDB.cpp
index 2a202f230..fa327cb48 100644
--- a/src/mesh/NodeDB.cpp
+++ b/src/mesh/NodeDB.cpp
@@ -103,13 +103,16 @@ void NodeDB::resetRadioConfig()
     crypto->setKey(channelSettings.psk.size, channelSettings.psk.bytes);
 
     // temp hack for quicker testing
+    // devicestate.no_save = TRUE;
+    if (devicestate.no_save) {
+        DEBUG_MSG("***** DEVELOPMENT MODE - DO NOT RELEASE *****");
 
-    /*
-    radioConfig.preferences.screen_on_secs = 30;
-    radioConfig.preferences.wait_bluetooth_secs = 30;
-    radioConfig.preferences.position_broadcast_secs = 6 * 60;
-    radioConfig.preferences.ls_secs = 60;
-    */
+        // Sleep quite frequently to stress test the BLE comms, broadcast position every 6 mins
+        radioConfig.preferences.screen_on_secs = 30;
+        radioConfig.preferences.wait_bluetooth_secs = 30;
+        radioConfig.preferences.position_broadcast_secs = 6 * 60;
+        radioConfig.preferences.ls_secs = 60;
+    }
 }
 
 void NodeDB::installDefaultDeviceState()
@@ -257,32 +260,36 @@ void NodeDB::loadFromDisk()
 void NodeDB::saveToDisk()
 {
 #ifdef FS
-    auto f = FS.open(preftmp, FILE_O_WRITE);
-    if (f) {
-        DEBUG_MSG("Writing preferences\n");
+    if (!devicestate.no_save) {
+        auto f = FS.open(preftmp, FILE_O_WRITE);
+        if (f) {
+            DEBUG_MSG("Writing preferences\n");
 
-        pb_ostream_t stream = {&writecb, &f, SIZE_MAX, 0};
+            pb_ostream_t stream = {&writecb, &f, SIZE_MAX, 0};
 
-        // DEBUG_MSG("Presave channel name=%s\n", channelSettings.name);
+            // DEBUG_MSG("Presave channel name=%s\n", channelSettings.name);
 
-        devicestate.version = DEVICESTATE_CUR_VER;
-        if (!pb_encode(&stream, DeviceState_fields, &devicestate)) {
-            DEBUG_MSG("Error: can't write protobuf %s\n", PB_GET_ERROR(&stream));
-            // FIXME - report failure to phone
+            devicestate.version = DEVICESTATE_CUR_VER;
+            if (!pb_encode(&stream, DeviceState_fields, &devicestate)) {
+                DEBUG_MSG("Error: can't write protobuf %s\n", PB_GET_ERROR(&stream));
+                // FIXME - report failure to phone
 
-            f.close();
+                f.close();
+            } else {
+                // Success - replace the old file
+                f.close();
+
+                // brief window of risk here ;-)
+                if (!FS.remove(preffile))
+                    DEBUG_MSG("Warning: Can't remove old pref file\n");
+                if (!FS.rename(preftmp, preffile))
+                    DEBUG_MSG("Error: can't rename new pref file\n");
+            }
         } else {
-            // Success - replace the old file
-            f.close();
-
-            // brief window of risk here ;-)
-            if (!FS.remove(preffile))
-                DEBUG_MSG("Warning: Can't remove old pref file\n");
-            if (!FS.rename(preftmp, preffile))
-                DEBUG_MSG("Error: can't rename new pref file\n");
+            DEBUG_MSG("ERROR: can't write prefs\n"); // FIXME report to app
         }
     } else {
-        DEBUG_MSG("ERROR: can't write prefs\n"); // FIXME report to app
+        DEBUG_MSG("***** DEVELOPMENT MODE - DO NOT RELEASE - not saving to flash *****");
     }
 #else
     DEBUG_MSG("ERROR filesystem not implemented\n");
diff --git a/src/mesh/mesh.pb.h b/src/mesh/mesh.pb.h
index 808ffab88..2093bd69c 100644
--- a/src/mesh/mesh.pb.h
+++ b/src/mesh/mesh.pb.h
@@ -188,6 +188,7 @@ typedef struct _DeviceState {
     bool has_rx_text_message;
     MeshPacket rx_text_message;
     uint32_t version;
+    bool no_save;
 } DeviceState;
 
 typedef struct _FromRadio {
@@ -245,7 +246,7 @@ typedef struct _ToRadio {
 #define RadioConfig_UserPreferences_init_default {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, "", "", 0, 0, {0, 0, 0}}
 #define NodeInfo_init_default                    {0, false, User_init_default, false, Position_init_default, 0, 0}
 #define MyNodeInfo_init_default                  {0, 0, 0, "", "", "", 0, 0, 0, 0, 0, 0, 0, 0}
-#define DeviceState_init_default                 {false, RadioConfig_init_default, false, MyNodeInfo_init_default, false, User_init_default, 0, {NodeInfo_init_default, NodeInfo_init_default, NodeInfo_init_default, NodeInfo_init_default, NodeInfo_init_default, NodeInfo_init_default, NodeInfo_init_default, NodeInfo_init_default, NodeInfo_init_default, NodeInfo_init_default, NodeInfo_init_default, NodeInfo_init_default, NodeInfo_init_default, NodeInfo_init_default, NodeInfo_init_default, NodeInfo_init_default, NodeInfo_init_default, NodeInfo_init_default, NodeInfo_init_default, NodeInfo_init_default, NodeInfo_init_default, NodeInfo_init_default, NodeInfo_init_default, NodeInfo_init_default, NodeInfo_init_default, NodeInfo_init_default, NodeInfo_init_default, NodeInfo_init_default, NodeInfo_init_default, NodeInfo_init_default, NodeInfo_init_default, NodeInfo_init_default}, 0, {MeshPacket_init_default}, false, MeshPacket_init_default, 0}
+#define DeviceState_init_default                 {false, RadioConfig_init_default, false, MyNodeInfo_init_default, false, User_init_default, 0, {NodeInfo_init_default, NodeInfo_init_default, NodeInfo_init_default, NodeInfo_init_default, NodeInfo_init_default, NodeInfo_init_default, NodeInfo_init_default, NodeInfo_init_default, NodeInfo_init_default, NodeInfo_init_default, NodeInfo_init_default, NodeInfo_init_default, NodeInfo_init_default, NodeInfo_init_default, NodeInfo_init_default, NodeInfo_init_default, NodeInfo_init_default, NodeInfo_init_default, NodeInfo_init_default, NodeInfo_init_default, NodeInfo_init_default, NodeInfo_init_default, NodeInfo_init_default, NodeInfo_init_default, NodeInfo_init_default, NodeInfo_init_default, NodeInfo_init_default, NodeInfo_init_default, NodeInfo_init_default, NodeInfo_init_default, NodeInfo_init_default, NodeInfo_init_default}, 0, {MeshPacket_init_default}, false, MeshPacket_init_default, 0, 0}
 #define DebugString_init_default                 {""}
 #define FromRadio_init_default                   {0, 0, {MeshPacket_init_default}}
 #define ToRadio_init_default                     {0, {MeshPacket_init_default}}
@@ -261,7 +262,7 @@ typedef struct _ToRadio {
 #define RadioConfig_UserPreferences_init_zero    {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, "", "", 0, 0, {0, 0, 0}}
 #define NodeInfo_init_zero                       {0, false, User_init_zero, false, Position_init_zero, 0, 0}
 #define MyNodeInfo_init_zero                     {0, 0, 0, "", "", "", 0, 0, 0, 0, 0, 0, 0, 0}
-#define DeviceState_init_zero                    {false, RadioConfig_init_zero, false, MyNodeInfo_init_zero, false, User_init_zero, 0, {NodeInfo_init_zero, NodeInfo_init_zero, NodeInfo_init_zero, NodeInfo_init_zero, NodeInfo_init_zero, NodeInfo_init_zero, NodeInfo_init_zero, NodeInfo_init_zero, NodeInfo_init_zero, NodeInfo_init_zero, NodeInfo_init_zero, NodeInfo_init_zero, NodeInfo_init_zero, NodeInfo_init_zero, NodeInfo_init_zero, NodeInfo_init_zero, NodeInfo_init_zero, NodeInfo_init_zero, NodeInfo_init_zero, NodeInfo_init_zero, NodeInfo_init_zero, NodeInfo_init_zero, NodeInfo_init_zero, NodeInfo_init_zero, NodeInfo_init_zero, NodeInfo_init_zero, NodeInfo_init_zero, NodeInfo_init_zero, NodeInfo_init_zero, NodeInfo_init_zero, NodeInfo_init_zero, NodeInfo_init_zero}, 0, {MeshPacket_init_zero}, false, MeshPacket_init_zero, 0}
+#define DeviceState_init_zero                    {false, RadioConfig_init_zero, false, MyNodeInfo_init_zero, false, User_init_zero, 0, {NodeInfo_init_zero, NodeInfo_init_zero, NodeInfo_init_zero, NodeInfo_init_zero, NodeInfo_init_zero, NodeInfo_init_zero, NodeInfo_init_zero, NodeInfo_init_zero, NodeInfo_init_zero, NodeInfo_init_zero, NodeInfo_init_zero, NodeInfo_init_zero, NodeInfo_init_zero, NodeInfo_init_zero, NodeInfo_init_zero, NodeInfo_init_zero, NodeInfo_init_zero, NodeInfo_init_zero, NodeInfo_init_zero, NodeInfo_init_zero, NodeInfo_init_zero, NodeInfo_init_zero, NodeInfo_init_zero, NodeInfo_init_zero, NodeInfo_init_zero, NodeInfo_init_zero, NodeInfo_init_zero, NodeInfo_init_zero, NodeInfo_init_zero, NodeInfo_init_zero, NodeInfo_init_zero, NodeInfo_init_zero}, 0, {MeshPacket_init_zero}, false, MeshPacket_init_zero, 0, 0}
 #define DebugString_init_zero                    {""}
 #define FromRadio_init_zero                      {0, 0, {MeshPacket_init_zero}}
 #define ToRadio_init_zero                        {0, {MeshPacket_init_zero}}
@@ -353,6 +354,7 @@ typedef struct _ToRadio {
 #define DeviceState_receive_queue_tag            5
 #define DeviceState_version_tag                  8
 #define DeviceState_rx_text_message_tag          7
+#define DeviceState_no_save_tag                  9
 #define FromRadio_packet_tag                     2
 #define FromRadio_my_info_tag                    3
 #define FromRadio_node_info_tag                  4
@@ -501,7 +503,8 @@ X(a, STATIC,   OPTIONAL, MESSAGE,  owner,             3) \
 X(a, STATIC,   REPEATED, MESSAGE,  node_db,           4) \
 X(a, STATIC,   REPEATED, MESSAGE,  receive_queue,     5) \
 X(a, STATIC,   OPTIONAL, MESSAGE,  rx_text_message,   7) \
-X(a, STATIC,   SINGULAR, UINT32,   version,           8)
+X(a, STATIC,   SINGULAR, UINT32,   version,           8) \
+X(a, STATIC,   SINGULAR, BOOL,     no_save,           9)
 #define DeviceState_CALLBACK NULL
 #define DeviceState_DEFAULT NULL
 #define DeviceState_radio_MSGTYPE RadioConfig
@@ -599,7 +602,7 @@ extern const pb_msgdesc_t ManufacturingData_msg;
 #define RadioConfig_UserPreferences_size         188
 #define NodeInfo_size                            132
 #define MyNodeInfo_size                          110
-#define DeviceState_size                         5401
+#define DeviceState_size                         5403
 #define DebugString_size                         258
 #define FromRadio_size                           322
 #define ToRadio_size                             316