diff --git a/docs/Repeater_CLI_commands.md b/docs/Repeater_CLI_commands.md
index 4a96025..adc09a9 100644
--- a/docs/Repeater_CLI_commands.md
+++ b/docs/Repeater_CLI_commands.md
@@ -26,6 +26,7 @@ All commands are sent over USB serial (CDC-ACM). Commands sent remotely over the
 |---------|-------------|
 | `ver` | Firmware version and build date |
 | `board` | Board manufacturer name |
+| `power` | Power sources, as upstream: `batt:<mV> mV usb:<yes\|no\|n/a> solar_chg:<yes\|no\|n/a> ext:<yes\|no> charger:<yes\|no>`. `usb` is the nRF52 VBUS detect (`n/a` on other chips); no board reports a solar-charger or charging line yet, so `solar_chg` is `n/a` and `charger` is `no` everywhere. `ext` is the same signal the low-battery shutdown checks |
 | `reboot` | Reboot immediately |
 | `poweroff` / `shutdown` | Power the node off, as upstream: GPS, sensor and buzzer rails off, LoRa held in reset, then System OFF (the power latch released first on soft-power boards). Wake with the user button (nRF) or a power cycle — a node without a reachable button stays off until someone gets to it, so think twice before sending it over remote admin. The shutdown reason `User Request` is recorded for `get pwrmgt.bootreason`. Replies `OK - powering off`; deferred like `reboot` |
 | `start dfu` | nRF52: reboot into the UF2 bootloader for drag-and-drop update. ESP32-S3: reboot into the ROM download mode on USB-Serial-JTAG (`303a:1001`), so ordinary `esptool write-flash` and browser flashers can reach the chip. Every other chip replies with an error and does **not** reboot — ESP32-C3/C6 and classic ESP32 never lose the port to USB OTG so esptool resets them itself, and nRF54L15/MG24/STM32WL have no USB device peripheral and are flashed over SWD |
@@ -150,6 +151,7 @@ Regions control which flood packets the repeater forwards. The region tree is hi
 |---------|-------------|
 | `gps` | GPS status in upstream's form: `on, active\|standby, fix\|no fix, N sats`, `off`, or `Can't find GPS`. `standby` (upstream: `deactivated`) means on but asleep between duty-cycle fixes |
 | `get gps` | The detail: `> on state=<off\|standby\|acquiring> sats=N fix=Ns ago lat= lon=`, or `no fix next=Ns` (seconds to the next wake) |
+| `gps diag` | Receiver liveness, in upstream's key form: `req:<0\|1> en:<0\|1> ok:<n> sat:<n> fix:<0\|1> fa:<ms\|never> bc:<n> sc:<n>`. `req` is the requested setting, `en` the module powered and searching (0 in duty-cycle standby), `ok` NMEA sentences the driver has parsed since boot (a count that stops rising means the module or its UART went silent, whatever `sat` says), `fa` the age of the last validated fix, `bc`/`sc` module power-on/off counts. Upstream's UART byte and bad-checksum counters are absent: the GNSS driver only passes valid sentences. Module configuration results are `get gps diag` |
 | `gps sync` | Take a fresh fix now (wake the GPS or extend its window); the fix sets the clock. `gps is off` / `gps provider not found` otherwise |
 | `gps on` | Enable GPS module |
 | `gps off` | Disable GPS module. Persisted: a repeater or room server with GPS off stays off across reboots. Boards whose GPS has no power line (RAK4631, RAK3401 1W, Station G2) put the module to sleep over UART |
@@ -189,7 +191,7 @@ Sample reply:
 
 **`sent=` proves transmission, not acceptance.** Only `sys=` shows what the module actually did. A module still running its factory or previously saved configuration reports `G` non-zero with the rest at `0`. Note `B0` is expected on u-blox M8 (BeiDou is deliberately disabled — only three major constellations can run concurrently), and `?0` is normal outside Japan (QZSS is regional).
 
-The generic-NMEA path sends three protocols — PMTK (MediaTek), PCAS (CASIC: Quectel L76K/L76KB, Air530Z) and UBX (u-blox) — because a WisBlock-style GPS slot can hold any of them and each family ignores what it does not understand. Related build option: `CONFIG_ZEPHCORE_GPS_NAV_MODE` sets the CASIC navigation dynamic model (`$PCAS11`), defaulting to stationary for repeaters and room servers and automotive otherwise. It is worth setting because that model is stored *in the module* and survives reflashing the host — a slot module that previously lived in another device can arrive stuck in an airborne model that quietly degrades fixes on a fixed site.
+The generic-NMEA path sends three protocols — PMTK (MediaTek), PCAS (CASIC: Quectel L76K/L76KB, Air530Z) and UBX (u-blox) — because a WisBlock-style GPS slot can hold any of them and each family ignores what it does not understand. Related build option: `CONFIG_ZEPHCORE_GPS_NAV_MODE` sets the CASIC navigation dynamic model (`$PCAS11`), defaulting to stationary for repeaters and room servers and automotive otherwise. It is worth setting because that model is stored *in the module* and survives reflashing the host — a slot module that previously lived in another device can arrive stuck in an airborne model that quietly degrades fixes on a fixed site. CASIC modules do not save the other settings, so about a second after every GPS power-on (`gps on` and each duty-cycle wake) the sentence selection, navigation model and constellation set (`$PCAS03`, `$PCAS11`, `$PCAS04`; on generic-NMEA boards also MediaTek's constellations, EASY and AIC) are written again; a board whose standby cuts the supply would otherwise fall back to GPS + BeiDou after its first sleep. Every GNSS board does this by default (`CONFIG_ZEPHCORE_GPS_REAPPLY`); other receivers ignore the sentences.
 
 Caveats: the `sys=` tally needs `CONFIG_ZEPHCORE_GPS_SAT_DIAG` (default on for repeaters, off for companions to save RAM) — the reply says so when built without it. Only the raw-UART path is re-run on `gps on`; boards with a real GNSS driver (Air530Z, LC76G) keep reporting their boot-time result, because that path goes through `modem_chat_run_script()`, which is safe only at boot. On those boards `E0` is also expected — the Air530Z driver supports GPS/GLONASS/BeiDou but not Galileo, and the firmware falls back automatically.
 
diff --git a/zephcore/Kconfig b/zephcore/Kconfig
index e5ec881..444b11d 100644
--- a/zephcore/Kconfig
+++ b/zephcore/Kconfig
@@ -1016,6 +1016,40 @@ config ZEPHCORE_GPS_SAT_DIAG
 	  available — this option only adds the per-constellation evidence to
 	  its report.
 
+config ZEPHCORE_GPS_REAPPLY
+	bool "Re-send GNSS module settings after every GPS power-on"
+	depends on GNSS
+	default y
+	help
+	  CASIC receivers (Quectel L76K/L76KB, Air530Z) keep the sentence
+	  selection (PCAS03) and constellation set (PCAS04) in RAM only: nothing
+	  here sends PCAS00 to save them, so a supply cut returns the module to
+	  its factory GPS + BeiDou. Configuration otherwise runs once, at boot,
+	  so a board whose gps off / duty-cycle standby really removes power
+	  would lose GLONASS after its first sleep (upstream MeshCore #3201
+	  re-sends PCAS04 on every start for the same reason).
+
+	  With this on, about one second after each power-on the settings that
+	  are lost with power are written again, blind, one sentence at a time
+	  with the boot sequence's settle gaps, over the GNSS UART from the main
+	  thread (never through modem_chat, whose blocking scripts are unsafe
+	  right after a power restore): PCAS03, PCAS11 (the nav mode, when set)
+	  and PCAS04 last; on generic-NMEA boards, whose module is unknown,
+	  MediaTek's PMTK353 constellations, EASY (PMTK869) and AIC (PMTK286)
+	  first. Both constellation commands restart their own chip's engine; on
+	  a module that kept its settings that is one restart per wake, taken
+	  over leaving one that lost them searching GPS-only. UBX stays
+	  boot-only: CFG-CFG saves it to the module's flash, and repeating it
+	  would wear that flash.
+
+	  No board list: every GNSS board gets it, and it is inert where it is
+	  not needed: receivers ignore the other families' sentences, and one
+	  that only went to standby (Wio Tracker L1's WAKEUP pin) is simply told
+	  what it already has. Costs under 130 UART bytes per wake.
+
+	  Turn it off in a board.conf only with a reason, e.g. a CASIC board
+	  proven to lose fixes to the navigation restart PCAS04 triggers.
+
 endmenu
 
 menu "WiFi OTA Update"
diff --git a/zephcore/adapters/board/ZephyrBoard.cpp b/zephcore/adapters/board/ZephyrBoard.cpp
index 64ba2b0..af59f9d 100644
--- a/zephcore/adapters/board/ZephyrBoard.cpp
+++ b/zephcore/adapters/board/ZephyrBoard.cpp
@@ -641,4 +641,14 @@ bool ZephyrBoard::isExternalPowered()
 #endif
 }
 
+bool ZephyrBoard::hasUsbPowerDetect() const
+{
+	return IS_ENABLED(CONFIG_SOC_SERIES_NRF52);
+}
+
+bool ZephyrBoard::isUsbPowered()
+{
+	return hasUsbPowerDetect() && isExternalPowered();
+}
+
 } /* namespace mesh */
diff --git a/zephcore/adapters/board/ZephyrBoard.h b/zephcore/adapters/board/ZephyrBoard.h
index 368e5dd..6242aaa 100644
--- a/zephcore/adapters/board/ZephyrBoard.h
+++ b/zephcore/adapters/board/ZephyrBoard.h
@@ -33,6 +33,10 @@ public:
 	void clearBootloaderMagic();      /* Clear stale GPREGRET values at startup */
 	uint8_t getStartupReason() const override;
 	bool isExternalPowered() override;  /* nRF52: VBUS present (USB/charger); else false */
+	/* `power`: nRF52's VBUS detect is a USB-power detect; other platforms
+	 * keep upstream's "n/a". No board reports a charger line yet. */
+	bool hasUsbPowerDetect() const override;
+	bool isUsbPowered() override;
 
 	/* get pwrmgt.*: upstream's power-management getters. */
 	uint16_t getBootVoltage() override { return _boot_mv; }
diff --git a/zephcore/adapters/gps/ZephyrGPSManager.cpp b/zephcore/adapters/gps/ZephyrGPSManager.cpp
index a508400..6d7557a 100644
--- a/zephcore/adapters/gps/ZephyrGPSManager.cpp
+++ b/zephcore/adapters/gps/ZephyrGPSManager.cpp
@@ -56,6 +56,7 @@ static gps_event_callback_t gps_event_cb = NULL;
 #define GPS_ACTION_TIMEOUT  BIT(1)  /* Acquisition timeout → go to standby */
 #define GPS_ACTION_FIX_DONE BIT(2)  /* Got enough good fixes → go to standby */
 #define GPS_ACTION_FIX      BIT(3)  /* A validated fix for gps_fix_cb (fix_pending) */
+#define GPS_ACTION_REAPPLY  BIT(4)  /* Next module re-send step (gps_reapply_step) */
 static atomic_t pending_gps_actions;
 
 /* GPS Power Management State Machine */
@@ -122,6 +123,42 @@ static void gps_start_acquiring(void);
 static K_WORK_DELAYABLE_DEFINE(gps_wake_work, gps_wake_work_fn);
 static K_WORK_DELAYABLE_DEFINE(gps_timeout_work, gps_timeout_work_fn);
 
+#if HAS_GPS_UART && defined(CONFIG_ZEPHCORE_GPS_REAPPLY)
+/* CONFIG_ZEPHCORE_GPS_REAPPLY: after each power-on, wait for the module
+ * to boot, then hand the main thread one sentence per step. */
+#define GPS_REAPPLY_BOOT_MS  1000  /* module boot is ~300 ms; margin for slow rails */
+static uint8_t gps_reapply_step;
+static uint32_t gps_reapply_count;  /* completed re-sends, `gps diag` ra: */
+static void gps_reapply_work_fn(struct k_work *work)
+{
+	ARG_UNUSED(work);
+
+	if (gps_current_state != GPS_STATE_ACQUIRING) {
+		return;
+	}
+	atomic_or(&pending_gps_actions, GPS_ACTION_REAPPLY);
+	if (gps_event_cb) {
+		gps_event_cb();
+	}
+}
+static K_WORK_DELAYABLE_DEFINE(gps_reapply_work, gps_reapply_work_fn);
+
+static void gps_reapply_start(void)
+{
+	gps_reapply_step = 0;
+	k_work_reschedule(&gps_reapply_work, K_MSEC(GPS_REAPPLY_BOOT_MS));
+}
+
+static void gps_reapply_cancel(void)
+{
+	k_work_cancel_delayable(&gps_reapply_work);
+	atomic_and(&pending_gps_actions, ~GPS_ACTION_REAPPLY);
+}
+#else
+static inline void gps_reapply_start(void) { }
+static inline void gps_reapply_cancel(void) { }
+#endif
+
 #else
 static gps_enable_callback_t gps_enable_cb = NULL;
 #endif
@@ -490,6 +527,7 @@ static void gps_go_to_standby(void)
 	 *   VBACKUP charger keeps the receiver's V_BCKP domain alive, so ephemeris/
 	 *   RTC survive the cut and re-acquisition is a warm/hot start, not cold.
 	 * Other non-GPIO boards: software sleep via UART commands (PMTK + UBX). */
+	gps_reapply_cancel();
 	gps_module_power(false);
 
 	/* Module is off/asleep — release the UART until the next wake
@@ -497,10 +535,10 @@ static void gps_go_to_standby(void)
 	gps_uart_set_power(false);
 	gps_hold_sleep_lock(false);
 
-	/* NOTE: gnss_configured stays true — L76K retains PCAS settings in
-	 * flash across power cycles. Re-running gps_module_configure() after GPIO
-	 * wake would call modem_chat_run_script() before the chip has booted,
-	 * risking a deadlock (modem_chat blocks on system work queue). */
+	/* NOTE: gnss_configured stays true, gps_module_configure() is boot-only:
+	 * after a power restore modem_chat_run_script() would reach a chip that
+	 * has not booted yet (deadlock risk, see gps_wake_work_fn). What a power
+	 * cut loses on CASIC parts is re-sent by gps_reapply_start() instead. */
 
 	/* Schedule next wake (event-driven, no polling!) */
 	k_work_schedule(&gps_wake_work, K_MSEC(wake_interval));
@@ -509,11 +547,12 @@ static void gps_go_to_standby(void)
 /* Wake GPS and start acquiring.
  * GPIO boards: hardware power-on.
  * Non-GPIO boards: UART wake byte (wakes L76K from standby, ZOE-M8Q from backup).
- * Does NOT call gps_module_configure() — constellation/fix-rate settings persist
- * in L76K flash across power cycles. Calling modem_chat_run_script() here
+ * Does NOT call gps_module_configure(). Calling modem_chat_run_script() here
  * would deadlock: the chip needs ~300ms to boot after GPIO power restore,
  * but modem_chat blocks the calling thread waiting for the system work
- * queue which may be processing stale UART data. */
+ * queue which may be processing stale UART data. CASIC settings are NOT
+ * persisted (no PCAS00, see the air530z driver), so they are re-sent blind
+ * a second after power-on (CONFIG_ZEPHCORE_GPS_REAPPLY). */
 static void gps_start_acquiring(void)
 {
 	LOG_INF("GPS: Waking for %s", gps_repeater_mode ? "time sync" : "position fix");
@@ -526,6 +565,7 @@ static void gps_start_acquiring(void)
 	 * goes out, so the first NMEA sentences aren't lost. */
 	gps_uart_set_power(true);
 	gps_module_power(true);
+	gps_reapply_start();
 
 	/* Schedule the standby timeout — unless always-on (interval 0), where the
 	 * GPS stays in continuous acquisition and never sleeps. Every duty window
@@ -824,8 +864,8 @@ void gps_enable(bool enable)
 		 * lock, and the first (longer) acquire window unless always-on. */
 		gps_start_acquiring();
 
-		/* gps_module_configure() runs once at boot (see gps_manager_init path).
-		 * L76K retains PCAS settings in flash across power cycles.
+		/* gps_module_configure() runs once at boot (see gps_manager_init path);
+		 * gps_start_acquiring() re-sends the CASIC settings a power cut loses.
 		 * Do NOT call modem_chat_run_script() here — the chip needs
 		 * ~300ms to boot after GPIO power restore and calling it
 		 * immediately deadlocks the main thread. */
@@ -836,6 +876,7 @@ void gps_enable(bool enable)
 		/* Cancel any pending work */
 		k_work_cancel_delayable(&gps_wake_work);
 		k_work_cancel_delayable(&gps_timeout_work);
+		gps_reapply_cancel();
 
 		/* Power off GPS — warm standby if VRTC available (Arduino sleep_gps),
 		 * full power off otherwise. Warm standby preserves ephemeris/RTC
@@ -1046,6 +1087,56 @@ void gps_get_state_info(struct gps_state_info *info)
 #endif
 }
 
+#if HAS_GNSS
+/* Parsed-sentence count from the GNSS driver (see gps_module_cfg.cpp). */
+extern "C" uint32_t zephcore_gnss_rx_count(void) __attribute__((weak));
+#endif
+
+void gps_format_diagnostics(char *out, size_t out_size)
+{
+	if (out_size == 0) {
+		return;
+	}
+#if HAS_GNSS
+	/* Upstream's keys, where this port has the same quantity: en = module
+	 * powered and searching (standby is off/asleep), ok = checksum-valid
+	 * sentences (the driver parses nothing else), fa = age of the last
+	 * validated fix. */
+	k_mutex_lock(&gps_mutex, K_FOREVER);
+	bool fix = current_pos.valid;
+	unsigned sats = current_pos.satellites;
+	k_mutex_unlock(&gps_mutex);
+
+	char fix_age[11];
+	if (last_fix_uptime_ms > 0) {
+		snprintf(fix_age, sizeof(fix_age), "%lu",
+			 (unsigned long)(uint32_t)(k_uptime_get() - last_fix_uptime_ms));
+	} else {
+		snprintf(fix_age, sizeof(fix_age), "never");
+	}
+
+	char ok[16] = "";
+	if (zephcore_gnss_rx_count != NULL) {
+		snprintf(ok, sizeof(ok), " ok:%lu", (unsigned long)zephcore_gnss_rx_count());
+	}
+
+	/* ZephCore addition: completed CASIC re-sends (CONFIG_ZEPHCORE_GPS_REAPPLY),
+	 * one per power-on that stayed up past GPS_REAPPLY_BOOT_MS. */
+	char ra[16] = "";
+#if HAS_GPS_UART && defined(CONFIG_ZEPHCORE_GPS_REAPPLY)
+	snprintf(ra, sizeof(ra), " ra:%lu", (unsigned long)gps_reapply_count);
+#endif
+
+	snprintf(out, out_size, "en:%u%s sat:%u fix:%u fa:%s bc:%lu sc:%lu%s",
+		 gps_current_state == GPS_STATE_ACQUIRING ? 1U : 0U,
+		 ok, sats, fix ? 1U : 0U, fix_age,
+		 (unsigned long)gps_power_on_count,
+		 (unsigned long)gps_power_off_count, ra);
+#else
+	snprintf(out, out_size, "en:0 sat:0 fix:0");
+#endif
+}
+
 /* Process pending GPS state transitions — called from main thread.
  * Work handlers on the system work queue set flags + signal the main
  * thread via gps_event_cb(). The main thread then calls this function,
@@ -1089,5 +1180,18 @@ void gps_process_event(void)
 			gps_go_to_standby();
 		}
 	}
+
+#if HAS_GPS_UART && defined(CONFIG_ZEPHCORE_GPS_REAPPLY)
+	/* After the transitions: a standby above has already cancelled it. */
+	if ((actions & GPS_ACTION_REAPPLY) && gps_current_state == GPS_STATE_ACQUIRING) {
+		uint32_t gap_ms = gps_module_reapply_step(gps_reapply_step++);
+
+		if (gap_ms > 0) {
+			k_work_reschedule(&gps_reapply_work, K_MSEC(gap_ms));
+		} else {
+			gps_reapply_count++;
+		}
+	}
+#endif
 #endif
 }
diff --git a/zephcore/adapters/gps/ZephyrGPSManager.h b/zephcore/adapters/gps/ZephyrGPSManager.h
index 4d80e2a..edaf622 100644
--- a/zephcore/adapters/gps/ZephyrGPSManager.h
+++ b/zephcore/adapters/gps/ZephyrGPSManager.h
@@ -53,6 +53,12 @@ void gps_set_diag(bool on);
  * succeeds; reports "never run" if configuration has not happened yet. */
 void gps_get_diag_report(char *buf, size_t len);
 
+/* `gps diag` (upstream's LocationProvider::formatDiagnostics): module on,
+ * NMEA sentences parsed, satellites, fix, fix age in ms, module power-on /
+ * power-off counts. Upstream's UART byte and bad-checksum counters have no
+ * source behind the GNSS API and are left out. */
+void gps_format_diagnostics(char *out, size_t out_size);
+
 /* GPS enable callback - called when GPS is enabled/disabled (for power management) */
 typedef void (*gps_enable_callback_t)(bool enabled);
 void gps_set_enable_callback(gps_enable_callback_t cb);
diff --git a/zephcore/adapters/gps/gps_internal.h b/zephcore/adapters/gps/gps_internal.h
index 3d01bbf..39596bc 100644
--- a/zephcore/adapters/gps/gps_internal.h
+++ b/zephcore/adapters/gps/gps_internal.h
@@ -84,6 +84,9 @@ void gps_sat_tally(uint8_t out[5]);
 void gps_power_control(bool on, bool keep_vrtc = false);
 /* The power line or rail if the board has one, else the UART sleep commands. */
 void gps_module_power(bool on, bool keep_vrtc = true);
+/* gps_module_power() calls, for `gps diag` (upstream's bc/sc). */
+extern uint32_t gps_power_on_count;
+extern uint32_t gps_power_off_count;
 /* Suspend/resume the GNSS UART (nRF UARTE: releases HFCLK). */
 void gps_uart_set_power(bool on);
 #if HAS_GPS_POWER_CONTROL
@@ -95,6 +98,12 @@ void gps_dump_gpio_states(void);
 void gps_module_configure(void);
 /* Re-run the UART configuration when `set gps diag 1` asked for it. */
 void gps_diag_maybe_reconfigure(void);
+#if HAS_GPS_UART && defined(CONFIG_ZEPHCORE_GPS_REAPPLY)
+/* CONFIG_ZEPHCORE_GPS_REAPPLY: write the step-th re-sent setting blind
+ * (see the list in gps_module_cfg.cpp). Returns the ms to wait before the
+ * next step, 0 when that was the last. */
+uint32_t gps_module_reapply_step(uint8_t step);
+#endif
 void gps_uart_dump_hw_state(void);
 #if HAS_GPS_UART
 extern const struct device *const gps_uart_dev;
diff --git a/zephcore/adapters/gps/gps_module_cfg.cpp b/zephcore/adapters/gps/gps_module_cfg.cpp
index 10f0276..260b1a4 100644
--- a/zephcore/adapters/gps/gps_module_cfg.cpp
+++ b/zephcore/adapters/gps/gps_module_cfg.cpp
@@ -29,9 +29,9 @@ static bool gps_diag_on = false;
  * 3. The script completion callback competes with NMEA processing
  *
  * Safe to call at boot because the driver init already ran and the chip
- * is powered and outputting NMEA. After power cycles, the L76K retains
- * constellation + fix rate settings in internal flash (PCAS commands
- * persist). So we only need to configure once. */
+ * is powered and outputting NMEA. PCAS settings are NOT persisted (nothing
+ * sends PCAS00), so what a power cut loses is re-sent blind after every
+ * power-on instead (gps_module_reapply_step, CONFIG_ZEPHCORE_GPS_REAPPLY). */
 static bool gnss_configured = false;
 
 /* ========== Configuration Diagnostics ==========
@@ -567,6 +567,65 @@ void gps_module_configure(void)
 	gnss_configured = true;
 }
 
+#if HAS_GPS_UART && defined(CONFIG_ZEPHCORE_GPS_REAPPLY)
+/* The boot-time settings a power cut loses (see the Kconfig help). One
+ * sentence per step, written with gps_uart_send() directly and no settle
+ * sleep: the caller waits each entry's gap with a work item, so the main
+ * thread only spends the UART time.
+ *
+ * Kept boot-only on purpose:
+ * - UBX: already saved to BBR + flash by CFG-CFG at boot, and repeating it
+ *   would rewrite the module's flash on every wake;
+ * - PCAS02 (1 Hz is the default) and PCAS06 (a query, no state).
+ *
+ * Both constellation commands restart their chip's navigation engine, and a
+ * sentence written into a restarting engine is lost, so each is followed by
+ * the boot sequence's restart settle: PMTK353 first, PCAS04 last. Each only
+ * restarts its own family's chip (the other ignores it). On a MediaTek part
+ * that merely slept this costs one engine restart per wake, accepted
+ * (architect, 2026-09-27): one that lost power is otherwise left searching
+ * GPS-only, which is slower than a restart with every constellation. The
+ * PMTK sentences go only where the module is unknown (the generic-NMEA
+ * path); an API-driver board's module is known CASIC. */
+struct reapply_cmd {
+	const char *sentence;
+	uint16_t gap_ms;        /* wait before the next one */
+};
+
+static const struct reapply_cmd reapply_casic[] = {
+	{ pcas_sentences, GPS_CFG_SETTLE_MS },
+#if CONFIG_ZEPHCORE_GPS_NAV_MODE >= 0
+	/* The driver's GNSS_LUATOS_AIR530Z_NAV_MODE mirrors this value, so
+	 * this matches what either path set at boot. */
+	{ pcas_nav_mode, GPS_CFG_SETTLE_MS },
+#endif
+	{ pcas_constellations, 0 },
+};
+static const struct reapply_cmd reapply_generic[] = {
+	{ pmtk_constellations, GPS_CFG_RESTART_MS },
+	{ pmtk_easy, GPS_CFG_SETTLE_MS },
+	{ pmtk_aic, GPS_CFG_SETTLE_MS },
+	{ pcas_sentences, GPS_CFG_SETTLE_MS },
+#if CONFIG_ZEPHCORE_GPS_NAV_MODE >= 0
+	{ pcas_nav_mode, GPS_CFG_SETTLE_MS },
+#endif
+	{ pcas_constellations, 0 },
+};
+
+uint32_t gps_module_reapply_step(uint8_t step)
+{
+	bool generic = (gps_cfg_diag.path == GPS_CFG_UART);
+	const struct reapply_cmd *list = generic ? reapply_generic : reapply_casic;
+	size_t n = generic ? ARRAY_SIZE(reapply_generic) : ARRAY_SIZE(reapply_casic);
+
+	if (step >= n) {
+		return 0;
+	}
+	gps_uart_send((const uint8_t *)list[step].sentence, strlen(list[step].sentence));
+	return (step + 1 < n) ? list[step].gap_ms : 0;
+}
+#endif
+
 /* ========== GPS UART Diagnostics ========== */
 
 /**
diff --git a/zephcore/adapters/gps/gps_power.cpp b/zephcore/adapters/gps/gps_power.cpp
index 0a3c98e..076d291 100644
--- a/zephcore/adapters/gps/gps_power.cpp
+++ b/zephcore/adapters/gps/gps_power.cpp
@@ -532,8 +532,16 @@ static void gps_software_wake(void)
 
 /* Module on or off with whatever this board has: the power GPIO or PMU rail,
  * else the UART sleep commands. keep_vrtc: T1000-E warm standby (off only). */
+uint32_t gps_power_on_count;
+uint32_t gps_power_off_count;
+
 void gps_module_power(bool on, bool keep_vrtc)
 {
+	if (on) {
+		gps_power_on_count++;
+	} else {
+		gps_power_off_count++;
+	}
 #if HAS_GPS_POWER_CONTROL || HAS_GPS_POWER_REGULATOR
 	gps_power_control(on, keep_vrtc);
 #elif HAS_GPS_UART
diff --git a/zephcore/app/CompanionMesh.cpp b/zephcore/app/CompanionMesh.cpp
index 88233b6..fea95bd 100644
--- a/zephcore/app/CompanionMesh.cpp
+++ b/zephcore/app/CompanionMesh.cpp
@@ -1453,6 +1453,20 @@ void CompanionMesh::onContactResponse(const ContactInfo &contact, const uint8_t
 		};
 		ui_notify_joystick_event(UI_JOYSTICK_REQ_RESPONSE, contact.id.pub_key, &rr);
 	}
+
+	/* Arduino b204f9a1: let the app know about unknown/unhandled responses
+	 * (eg. push telemetry from a sensor subscription): tag + payload as-is. */
+	{
+		uint8_t rsp[MAX_FRAME_SIZE];
+		int i = 0;
+		rsp[i++] = PUSH_CODE_BINARY_RESPONSE;
+		rsp[i++] = 0;  // reserved
+		int data_len = len;
+		if (data_len > (int)sizeof(rsp) - i) data_len = sizeof(rsp) - i;
+		memcpy(&rsp[i], data, data_len);
+		i += data_len;
+		sendPush(rsp[0], &rsp[1], i - 1);
+	}
 }
 
 /* Raw packet logging - sends all RX packets to app for "heard X repeats" etc */
diff --git a/zephcore/helpers/CommonCLI.cpp b/zephcore/helpers/CommonCLI.cpp
index d8503fa..6c238df 100644
--- a/zephcore/helpers/CommonCLI.cpp
+++ b/zephcore/helpers/CommonCLI.cpp
@@ -550,6 +550,19 @@ void CommonCLI::handleCommand(uint32_t sender_timestamp, const char* command, ch
 		snprintf(reply, CLI_REPLY_SIZE, "%s (Build: %s)", _callbacks->getFirmwareVer(), _callbacks->getBuildDate());
 	} else if (memcmp(command, "board", 5) == 0) {
 		snprintf(reply, CLI_REPLY_SIZE, "%s", _board->getManufacturerName());
+	} else if (strcmp(command, "power") == 0) {
+		const char* usb_state = _board->hasUsbPowerDetect()
+					    ? (_board->isUsbPowered() ? "yes" : "no")
+					    : "n/a";
+		const char* solar_state = _board->hasSolarChargerDetect()
+					      ? (_board->isSolarChargerActive() ? "yes" : "no")
+					      : "n/a";
+		snprintf(reply, 160, "batt:%u mV usb:%s solar_chg:%s ext:%s charger:%s",
+			 (unsigned)_board->getBattMilliVolts(),
+			 usb_state,
+			 solar_state,
+			 _board->isExternalPowered() ? "yes" : "no",
+			 _board->isChargerActive() ? "yes" : "no");
 	} else if (memcmp(command, "sensor get ", 11) == 0) {
 		const char* key = command + 11;
 		const char* val = _sensors->getSettingByKey(key);
@@ -621,6 +634,21 @@ void CommonCLI::handleCommand(uint32_t sender_timestamp, const char* command, ch
 			gps_request_fresh_fix();
 			strcpy(reply, "ok");
 		}
+	} else if (strcmp(command, "gps diag") == 0) {
+		/* ZEPHCORE: upstream asks the LocationProvider; here the GPS
+		 * manager formats the fields it has (see gps_format_diagnostics). */
+		if (_sensors->isGPSDetected()) {
+			const char* setting = _sensors->getSettingByKey("gps");
+			bool requested = setting != NULL && strcmp(setting, "1") == 0;
+			int prefix_len = snprintf(reply, 160, "req:%u ", requested ? 1U : 0U);
+			if (prefix_len < 0 || prefix_len >= 160) {
+				reply[159] = 0;
+			} else {
+				gps_format_diagnostics(reply + prefix_len, 160 - prefix_len);
+			}
+		} else {
+			strcpy(reply, "gps provider not found");
+		}
 	} else if (memcmp(command, "gps setloc", 10) == 0) {
 		_prefs->node_lat = _sensors->node_lat;
 		_prefs->node_lon = _sensors->node_lon;
diff --git a/zephcore/include/mesh/MeshCore.h b/zephcore/include/mesh/MeshCore.h
index 41e69cc..6124a50 100644
--- a/zephcore/include/mesh/MeshCore.h
+++ b/zephcore/include/mesh/MeshCore.h
@@ -81,6 +81,16 @@ public:
   // ZEPHCORE: no isPwrMgtInitialised() / getWakeLpcompSupported() -- upstream's
   // nRF52 Arduino power manager; Zephyr PM covers this.
   virtual bool isExternalPowered() { return false; }
+  // True while a board can identify an active battery-charging source.
+  virtual bool isChargerActive() { return false; }
+
+  // Optional, source-specific power detection. Boards that can distinguish a USB
+  // supply from a solar charger override these; defaults keep every other board
+  // unaffected (the generic CLI prints "n/a" when a capability is absent).
+  virtual bool hasUsbPowerDetect() const { return false; }
+  virtual bool isUsbPowered() { return false; }
+  virtual bool hasSolarChargerDetect() const { return false; }
+  virtual bool isSolarChargerActive() { return false; }
   virtual uint16_t getBootVoltage() { return 0; }
   virtual uint32_t getResetReason() const { return 0; }
   virtual const char* getResetReasonString(uint32_t reason) { return "Not available"; }