diff --git a/examples/companion_radio/MyMesh.cpp b/examples/companion_radio/MyMesh.cpp
index 1e4bf99a..f097df0a 100644
--- a/examples/companion_radio/MyMesh.cpp
+++ b/examples/companion_radio/MyMesh.cpp
@@ -402,7 +402,7 @@ static mesh::RadioParamApplyResult applyFixedRadioParams(float freq, float bw, u
 #endif
 int MyMesh::calcRxDelay(float score, uint32_t air_time) const {
   if (_prefs.rx_delay_base <= 0.0f) return 0;
-  return (int)((pow(_prefs.rx_delay_base, 0.85f - score) - 1.0) * air_time);
+  return (int)((powf(_prefs.rx_delay_base, 0.85f - score) - 1.0f) * air_time);
 }
 
 uint32_t MyMesh::getRetransmitDelay(const mesh::Packet *packet) {
diff --git a/examples/simple_repeater/MyMesh.cpp b/examples/simple_repeater/MyMesh.cpp
index ce87b089..10d4dff4 100644
--- a/examples/simple_repeater/MyMesh.cpp
+++ b/examples/simple_repeater/MyMesh.cpp
@@ -108,6 +108,12 @@
 #define FLOOD_PACKET_FILTER_LOGIN_PROTECTED_HOPS    7
 #define FLOOD_PACKET_FILTER_TXT_MSG_PROTECTED_HOPS  5
 #define DEFAULT_FLOOD_CHANNEL_BLOCK_NAME  "#wardriving"
+static const char FLOOD_PACKET_FILTER_USAGE[] =
+    "Err - use: set flood.filter[.n] <type> [hops] [path=blacklist] [scope=<name>] [require=region] [tx=slow] [suspend=tempradio]";
+static const char FLOOD_PACKET_FILTER_DUPLICATE[] =
+    "Err - duplicate filter option";
+static const char FLOOD_CHANNEL_SCOPE_USAGE[] =
+    "Err - use: set flood.channel.scope[.n] <match> <region> [path=blacklist|path=bucket:1-6] [tx=slow]";
 #ifndef DEFAULT_FLOOD_CHANNEL_BLOCK_HOPS
   #define DEFAULT_FLOOD_CHANNEL_BLOCK_HOPS 4
 #endif
@@ -1025,7 +1031,7 @@ void MyMesh::logTxFail(mesh::Packet *pkt, int len) {
 
 int MyMesh::calcRxDelay(float score, uint32_t air_time) const {
   if (_prefs.rx_delay_base <= 0.0f) return 0;
-  return (int)((pow(_prefs.rx_delay_base, 0.85f - score) - 1.0) * air_time);
+  return (int)((powf(_prefs.rx_delay_base, 0.85f - score) - 1.0f) * air_time);
 }
 
 bool MyMesh::evaluateScopeRewriteTiming(const mesh::Packet* packet,
@@ -1091,7 +1097,7 @@ int MyMesh::calcRxDelayForPacket(const mesh::Packet* packet, float score,
 
   float slow_base =
       FloodFilterPolicy::slowScopeRxDelayBase(_prefs.rx_delay_base);
-  return (int)((pow(slow_base, 0.85f - score) - 1.0f) * air_time);
+  return (int)((powf(slow_base, 0.85f - score) - 1.0f) * air_time);
 }
 
 uint32_t MyMesh::getRetransmitDelay(const mesh::Packet *packet) {
@@ -5047,7 +5053,7 @@ void MyMesh::setFloodPacketFilter(const char* args, char* reply) {
     }
     requested_slot = slot - 1;
     if (*cursor != ' ') {
-      strcpy(reply, "Err - expected packet type");
+      strcpy(reply, "Err - packet type must be name, any, 0-15, or 0x00-0x0F");
       return;
     }
   }
@@ -5075,7 +5081,7 @@ void MyMesh::setFloodPacketFilter(const char* args, char* reply) {
     token = separator;
   }
   if (token_count == 0) {
-    strcpy(reply, "Err - use: set flood.filter[.n] <type> [hops] [path=blacklist] [scope=<name>] [require=region] [tx=slow] [suspend=tempradio]");
+    strcpy(reply, FLOOD_PACKET_FILTER_USAGE);
     return;
   }
 
@@ -5098,25 +5104,25 @@ void MyMesh::setFloodPacketFilter(const char* args, char* reply) {
   for (int i = 1; i < token_count; i++) {
     if (floodFilterAsciiEqual(tokens[i], "suspend=tempradio")) {
       if (suspend_on_temp_radio) {
-        strcpy(reply, "Err - duplicate suspend=tempradio");
+        strcpy(reply, FLOOD_PACKET_FILTER_DUPLICATE);
         return;
       }
       suspend_on_temp_radio = true;
     } else if (floodFilterAsciiEqual(tokens[i], "path=blacklist")) {
       if (match_blacklisted_path) {
-        strcpy(reply, "Err - duplicate path=blacklist");
+        strcpy(reply, FLOOD_PACKET_FILTER_DUPLICATE);
         return;
       }
       match_blacklisted_path = true;
     } else if (floodFilterAsciiEqual(tokens[i], "require=region")) {
       if (scope_requires_region_match) {
-        strcpy(reply, "Err - duplicate require=region");
+        strcpy(reply, FLOOD_PACKET_FILTER_DUPLICATE);
         return;
       }
       scope_requires_region_match = true;
     } else if (floodFilterAsciiStartsWith(tokens[i], "tx=")) {
       if (scope_timing_set) {
-        strcpy(reply, "Err - duplicate tx timing");
+        strcpy(reply, FLOOD_PACKET_FILTER_DUPLICATE);
         return;
       }
       if (floodFilterAsciiEqual(tokens[i], "tx=slow")) {
@@ -5128,7 +5134,7 @@ void MyMesh::setFloodPacketFilter(const char* args, char* reply) {
       scope_timing_set = true;
     } else if (floodFilterAsciiStartsWith(tokens[i], "scope=")) {
       if (scope_name[0] != 0) {
-        strcpy(reply, "Err - duplicate scope");
+        strcpy(reply, FLOOD_PACKET_FILTER_DUPLICATE);
         return;
       }
       if (!normalizeFloodFilterScopeName(tokens[i] + strlen("scope="),
@@ -5139,7 +5145,7 @@ void MyMesh::setFloodPacketFilter(const char* args, char* reply) {
     } else if (!hops_set && parseFloodFilterHopSpec(tokens[i], min_hops, max_hops)) {
       hops_set = true;
     } else {
-      strcpy(reply, "Err - use optional hops, path=blacklist, scope=<name>, require=region, tx=slow, and suspend=tempradio");
+      strcpy(reply, FLOOD_PACKET_FILTER_USAGE);
       return;
     }
   }
@@ -5783,7 +5789,7 @@ void MyMesh::setFloodChannelScope(const char* args, char* reply) {
   char region_text[32];
   if (takeFloodModerationToken(cursor, channel_text, sizeof(channel_text)) != 1
       || takeFloodModerationToken(cursor, region_text, sizeof(region_text)) != 1) {
-    strcpy(reply, "Err - use: set flood.channel.scope[.n] <match> <region> [path=blacklist|path=bucket:1-6] [tx=slow]");
+    strcpy(reply, FLOOD_CHANNEL_SCOPE_USAGE);
     return;
   }
   bool slow_timing = false;
@@ -5825,12 +5831,12 @@ void MyMesh::setFloodChannelScope(const char* args, char* reply) {
       path_selector = (uint8_t)(
           FloodFilterPolicy::SCOPE_PATH_BRIDGE_BUCKET_BASE + bucket - 1U);
     } else {
-      strcpy(reply, "Err - scope option must be path=blacklist, path=bucket:1-6, or tx=fast|slow");
+      strcpy(reply, FLOOD_CHANNEL_SCOPE_USAGE);
       return;
     }
   }
   if (option_result < 0) {
-    strcpy(reply, "Err - use: set flood.channel.scope[.n] <match> <region> [path=blacklist|path=bucket:1-6] [tx=slow]");
+    strcpy(reply, FLOOD_CHANNEL_SCOPE_USAGE);
     return;
   }
 
diff --git a/examples/simple_room_server/MyMesh.cpp b/examples/simple_room_server/MyMesh.cpp
index f8ba69a9..ad8ec736 100644
--- a/examples/simple_room_server/MyMesh.cpp
+++ b/examples/simple_room_server/MyMesh.cpp
@@ -296,7 +296,7 @@ void MyMesh::logTxFail(mesh::Packet *pkt, int len) {
 
 int MyMesh::calcRxDelay(float score, uint32_t air_time) const {
   if (_prefs.rx_delay_base <= 0.0f) return 0;
-  return (int)((pow(_prefs.rx_delay_base, 0.85f - score) - 1.0) * air_time);
+  return (int)((powf(_prefs.rx_delay_base, 0.85f - score) - 1.0f) * air_time);
 }
 
 const char *MyMesh::getLogDateTime() {
diff --git a/examples/simple_sensor/SensorMesh.cpp b/examples/simple_sensor/SensorMesh.cpp
index 88c47de1..eac25a1c 100644
--- a/examples/simple_sensor/SensorMesh.cpp
+++ b/examples/simple_sensor/SensorMesh.cpp
@@ -354,7 +354,7 @@ bool SensorMesh::allowPacketForward(const mesh::Packet* packet) {
 
 int SensorMesh::calcRxDelay(float score, uint32_t air_time) const {
   if (_prefs.rx_delay_base <= 0.0f) return 0;
-  return (int) ((pow(_prefs.rx_delay_base, 0.85f - score) - 1.0) * air_time);
+  return (int) ((powf(_prefs.rx_delay_base, 0.85f - score) - 1.0f) * air_time);
 }
 
 uint32_t SensorMesh::getRetransmitDelay(const mesh::Packet* packet) {
diff --git a/src/Dispatcher.cpp b/src/Dispatcher.cpp
index edc42538..b6c1adac 100644
--- a/src/Dispatcher.cpp
+++ b/src/Dispatcher.cpp
@@ -91,7 +91,7 @@ void Dispatcher::restoreOutboundTxOverrides() {
 }
 
 int Dispatcher::calcRxDelay(float score, uint32_t air_time) const {
-  return (int) ((pow(10, 0.85f - score) - 1.0) * air_time);
+  return (int) ((powf(10.0f, 0.85f - score) - 1.0f) * air_time);
 }
 
 uint32_t Dispatcher::getCADFailRetryDelay() const {
@@ -101,6 +101,27 @@ uint32_t Dispatcher::getCADFailMaxDuration() const {
   return 4000;   // 4 seconds
 }
 
+#if MESH_PACKET_LOGGING
+void Dispatcher::logPacketStart(const char* direction, const Packet* packet, int len) {
+  Serial.print(getLogDateTime());
+  Serial.printf(": %s, len=%d (type=%d, route=%s, payload_len=%d)",
+                direction, len, packet->getPayloadType(),
+                packet->isRouteDirect() ? "D" : "F", packet->payload_len);
+}
+
+void Dispatcher::logPacketEnd(const Packet* packet) {
+  const uint8_t type = packet->getPayloadType();
+  if (packet->payload_len >= 2
+      && (type == PAYLOAD_TYPE_PATH || type == PAYLOAD_TYPE_REQ
+          || type == PAYLOAD_TYPE_RESPONSE || type == PAYLOAD_TYPE_TXT_MSG)) {
+    Serial.printf(" [%02X -> %02X]\n", (uint32_t)packet->payload[1],
+                  (uint32_t)packet->payload[0]);
+  } else {
+    Serial.write((uint8_t)'\n');
+  }
+}
+#endif
+
 bool Dispatcher::getNextQueueWakeDelay(uint32_t& delay_millis) const {
   const uint32_t now = _ms->getMillis();
   bool found = false;
@@ -416,23 +437,15 @@ void Dispatcher::checkRecv() {
   }
   if (pkt) {
     #if MESH_PACKET_LOGGING
-    Serial.print(getLogDateTime());
-    Serial.printf(": RX, len=%d (type=%d, route=%s, payload_len=%d) SNR=%d RSSI=%d score=%d time=%d", 
-            pkt->getRawLength(), pkt->getPayloadType(), pkt->isRouteDirect() ? "D" : "F", pkt->payload_len,
-            (int)pkt->getSNR(), (int)_radio->getLastRSSI(), (int)(score*1000), air_time);
+    logPacketStart("RX", pkt, pkt->getRawLength());
+    Serial.printf(" SNR=%d RSSI=%d score=%d time=%d", (int)pkt->getSNR(),
+                  (int)_radio->getLastRSSI(), (int)(score * 1000), air_time);
 
     static uint8_t packet_hash[MAX_HASH_SIZE];
     pkt->calculatePacketHash(packet_hash);
     Serial.print(" hash=");
     mesh::Utils::printHex(Serial, packet_hash, MAX_HASH_SIZE);
-
-    if (pkt->payload_len >= 2
-        && (pkt->getPayloadType() == PAYLOAD_TYPE_PATH || pkt->getPayloadType() == PAYLOAD_TYPE_REQ
-            || pkt->getPayloadType() == PAYLOAD_TYPE_RESPONSE || pkt->getPayloadType() == PAYLOAD_TYPE_TXT_MSG)) {
-      Serial.printf(" [%02X -> %02X]\n", (uint32_t)pkt->payload[1], (uint32_t)pkt->payload[0]);
-    } else {
-      Serial.printf("\n");
-    }
+    logPacketEnd(pkt);
     #endif
     logRx(pkt, pkt->getRawLength(), score);   // hook for custom logging
 
@@ -594,16 +607,8 @@ void Dispatcher::checkSend() {
       outbound_expiry = futureMillis(max_airtime);
 
     #if MESH_PACKET_LOGGING
-      Serial.print(getLogDateTime());
-      Serial.printf(": TX, len=%d (type=%d, route=%s, payload_len=%d)", 
-            len, outbound->getPayloadType(), outbound->isRouteDirect() ? "D" : "F", outbound->payload_len);
-      if (outbound->payload_len >= 2
-          && (outbound->getPayloadType() == PAYLOAD_TYPE_PATH || outbound->getPayloadType() == PAYLOAD_TYPE_REQ
-              || outbound->getPayloadType() == PAYLOAD_TYPE_RESPONSE || outbound->getPayloadType() == PAYLOAD_TYPE_TXT_MSG)) {
-        Serial.printf(" [%02X -> %02X]\n", (uint32_t)outbound->payload[1], (uint32_t)outbound->payload[0]);
-      } else {
-        Serial.printf("\n");
-      }
+      logPacketStart("TX", outbound, len);
+      logPacketEnd(outbound);
     #endif
     }
   }
diff --git a/src/Dispatcher.h b/src/Dispatcher.h
index b46c93f5..3101f22c 100644
--- a/src/Dispatcher.h
+++ b/src/Dispatcher.h
@@ -356,6 +356,11 @@ public:
   unsigned long futureMillis(int millis_from_now) const;
 
 private:
+#if MESH_PACKET_LOGGING
+  void logPacketStart(const char* direction, const Packet* packet, int len)
+      __attribute__((noinline));
+  void logPacketEnd(const Packet* packet) __attribute__((noinline));
+#endif
   void checkRecv();
   void checkSend();
 };
diff --git a/src/helpers/AutoDiscoverRTCClock.cpp b/src/helpers/AutoDiscoverRTCClock.cpp
index af08fddb..53e58dd4 100644
--- a/src/helpers/AutoDiscoverRTCClock.cpp
+++ b/src/helpers/AutoDiscoverRTCClock.cpp
@@ -87,8 +87,8 @@ void AutoDiscoverRTCClock::setCurrentTime(uint32_t time) {
     rtc_3231.adjust(DateTime(time));
   } else if (rv3028_success) {
     auto dt = DateTime(time);
-	  uint8_t weekday = (dt.day() + (uint16_t)((2.6 * dt.month()) - 0.2) - (2 * (dt.year() / 100)) + dt.year() + (uint16_t)(dt.year() / 4) + (uint16_t)(dt.year() / 400)) % 7;
-    rtc_rv3028.setTime(dt.year(), dt.month(), weekday, dt.day(), dt.hour(), dt.minute(), dt.second());
+    rtc_rv3028.setTime(dt.year(), dt.month(), dt.dayOfTheWeek(), dt.day(),
+                       dt.hour(), dt.minute(), dt.second());
   } else if (rtc_8563_success) {
     rtc_8563.adjust(DateTime(time));
   } else if (rtc_8130_success) {
diff --git a/src/helpers/RTC_RX8130CE.cpp b/src/helpers/RTC_RX8130CE.cpp
index 8aa2b1ff..c0361194 100644
--- a/src/helpers/RTC_RX8130CE.cpp
+++ b/src/helpers/RTC_RX8130CE.cpp
@@ -108,27 +108,27 @@ bool RTC_RX8130CE::setTime(struct tm *t) {
 }
 
 void RTC_RX8130CE::adjust(DateTime dt) {
-   struct tm *atv;
-   time_t utime;
-
-   utime = (time_t)dt.unixtime();
-   atv = gmtime(&utime);
-
-   this->setTime(atv);
+   struct tm atv = {};
+   atv.tm_sec = dt.second();
+   atv.tm_min = dt.minute();
+   atv.tm_hour = dt.hour();
+   atv.tm_wday = dt.dayOfTheWeek();
+   atv.tm_mday = dt.day();
+   atv.tm_mon = dt.month() - 1;
+   atv.tm_year = dt.year() - 1900;
+   this->setTime(&atv);
 }
 
 DateTime RTC_RX8130CE::now() {
    struct tm atv;
    this->getTime(&atv);
 
-   return DateTime((uint32_t)mktime(&atv));
+   return DateTime(atv.tm_year + 1900, atv.tm_mon + 1, atv.tm_mday,
+                   atv.tm_hour, atv.tm_min, atv.tm_sec);
 }
 
 uint32_t RTC_RX8130CE::unixtime() {
-   struct tm atv;
-   this->getTime(&atv);
-
-   return (uint32_t)mktime(&atv);
+   return now().unixtime();
 }
 
 bool RTC_RX8130CE::getTime(struct tm *t) {
diff --git a/src/helpers/ota/OtaCli.cpp b/src/helpers/ota/OtaCli.cpp
index 55a6f942..d8ed90c7 100644
--- a/src/helpers/ota/OtaCli.cpp
+++ b/src/helpers/ota/OtaCli.cpp
@@ -424,7 +424,9 @@ static bool handle_dev(const char* d, char* reply, OtaContext& c) {
   if (strncmp(d, "stage ", 6) == 0) {
     uint32_t sz = parse_u32(d + 6);
     if (sz == 0 || sz > OTA_SERVE_BUF_SIZE) { sprintf(reply, "ERR size 1..%u", OTA_SERVE_BUF_SIZE); }
-    else { memset(c.serve_buf, 0xFF, sz); c.serve_expected = sz; c.serving = false;
+    else if (!c.ensureServeBuffer()) { strcpy(reply, "ERR stage OOM"); }
+    else { c.manager.clear_primary(); c.serving = false;
+           memset(c.serve_buf, 0xFF, sz); c.serve_expected = sz;
            sprintf(reply, "OK stage %u bytes", (unsigned)sz); }
 
   } else if (strncmp(d, "recv ", 5) == 0) {
@@ -435,7 +437,7 @@ static bool handle_dev(const char* d, char* reply, OtaContext& c) {
     int blen = (int)strlen(hex) / 2;
     uint8_t tmp[80];
     if (blen <= 0 || blen > (int)sizeof(tmp) || !mesh::Utils::fromHex(tmp, blen, hex)) strcpy(reply, "ERR hex");
-    else if (off + blen > c.serve_expected) strcpy(reply, "ERR off>size (stage first)");
+    else if (!c.serve_buf || off + blen > c.serve_expected) strcpy(reply, "ERR off>size (stage first)");
     else { memcpy(c.serve_buf + off, tmp, blen); sprintf(reply, "OK %d@%u", blen, (unsigned)off); }
 
   } else if (strncmp(d, "serve self", 10) == 0) {     // host our own running firmware, served from flash
@@ -447,6 +449,10 @@ static bool handle_dev(const char* d, char* reply, OtaContext& c) {
       sprintf(reply, "OK serving self fw mid=%s (%u B, flash-backed) - peers can pull it", midhx, (unsigned)img);
     } else strcpy(reply, "ERR serve self (no EndF / image too big / OOM)");
   } else if (strncmp(d, "serve", 5) == 0) {
+    if (!c.serve_buf || c.serve_expected == 0) {
+      strcpy(reply, "ERR nothing staged");
+      return true;
+    }
     c.serving = c.manager.serve(c.serve_buf, c.serve_expected);
     if (!c.serving) { strcpy(reply, "ERR serve (bad .mota)"); return true; }
     VerifyResult r = ota_verify(c.serve_buf, c.serve_expected, c.allow);
@@ -466,7 +472,7 @@ static bool handle_dev(const char* d, char* reply, OtaContext& c) {
   } else if (strncmp(d, "verify", 6) == 0) {
     const uint8_t* buf; uint32_t len;
     if (c.manager.fetchState() == OtaManager::COMPLETE) { buf = c.fetch_store.data(); len = c.fetch_store.staged_size(); }
-    else { buf = c.serve_buf; len = c.serve_expected; }
+    else { buf = c.serve_buf; len = c.serve_buf ? c.serve_expected : 0; }
     if (len == 0 || !buf) { strcpy(reply, "ERR nothing to verify (flash-staged: applydelta verifies)"); return true; }
     VerifyResult r = ota_verify(buf, len, c.allow);
     sprintf(reply, "verify parsed=%d root=%d payload=%d img=%d signed=%d sig=%d trust=%d | ok=%d auto=%d",
@@ -486,7 +492,7 @@ static bool handle_dev(const char* d, char* reply, OtaContext& c) {
       if (ota_apply_slot_info(&addr, &size)) sprintf(reply, "inactive slot addr=0x%X size=%u", (unsigned)addr, (unsigned)size);
       else strcpy(reply, "ERR no A/B slot (apply unsupported on this build)");
     } else if (strncmp(sub, "manifest", 8) == 0) {
-      if (ota_apply_set_manifest(c.serve_buf, c.serve_expected, c.allow, c.apply_st))
+      if (c.serve_buf && ota_apply_set_manifest(c.serve_buf, c.serve_expected, c.allow, c.apply_st))
         sprintf(reply, "manifest ok img=%u sig=%d trust=%d", (unsigned)c.apply_st.image_size, c.apply_st.sig_ok, c.apply_st.trusted);
       else strcpy(reply, "ERR manifest parse / not full-image / unsupported");
     } else if (strncmp(sub, "verify", 6) == 0) {
@@ -501,7 +507,9 @@ static bool handle_dev(const char* d, char* reply, OtaContext& c) {
     }
 
   } else if (strncmp(d, "clear", 5) == 0) {
-    c.serve_expected = 0; c.serving = false; c.fetch_store.clear(); c.manager.reset_session();
+    c.manager.clear_primary();
+    c.serve_expected = 0; c.serving = false; c.releaseServeBuffer();
+    c.fetch_store.clear(); c.manager.reset_session();
     strcpy(reply, "OK cleared");
 
   } else {
diff --git a/src/helpers/ota/OtaContext.h b/src/helpers/ota/OtaContext.h
index b786c2fe..4b724b44 100644
--- a/src/helpers/ota/OtaContext.h
+++ b/src/helpers/ota/OtaContext.h
@@ -1,6 +1,7 @@
 #pragma once
 
 #include <stdio.h>          // snprintf (hw_id mismatch message)
+#include <stdlib.h>         // malloc/free (lazy ESP32 manual-stage buffer)
 #include <string.h>         // strncmp/strncpy (hw_id)
 #include "OtaManager.h"
 #include "OtaStore.h"
@@ -62,7 +63,24 @@ struct OtaContext {
   OtaStoreRam<OTA_FETCH_BUF_SIZE> fetch_store;
 #endif
   SignerAllowlist allow;
+#if defined(ESP32_PLATFORM)
+  // Manual `ota dev stage` is a diagnostic path. Reserving its full buffer in
+  // .bss prevents high-capacity classic ESP32 images from linking, even when
+  // the command is never used, so allocate it only while a manual stage exists.
+  uint8_t* serve_buf = nullptr;
+  bool ensureServeBuffer() {
+    if (!serve_buf) serve_buf = static_cast<uint8_t*>(malloc(OTA_SERVE_BUF_SIZE));
+    return serve_buf != nullptr;
+  }
+  void releaseServeBuffer() {
+    free(serve_buf);
+    serve_buf = nullptr;
+  }
+#else
   uint8_t  serve_buf[OTA_SERVE_BUF_SIZE];
+  bool ensureServeBuffer() { return true; }
+  void releaseServeBuffer() {}
+#endif
   uint32_t serve_expected = 0;   // size declared by `ota stage`
   bool     serving = false;      // manager.serve() succeeded
   // flash-backed self-serve: cached merkle leaves (heap, freed on re-serve) + assembled manifest of our
diff --git a/src/helpers/ota/OtaManager.cpp b/src/helpers/ota/OtaManager.cpp
index a1843a18..ad10bcf4 100644
--- a/src/helpers/ota/OtaManager.cpp
+++ b/src/helpers/ota/OtaManager.cpp
@@ -10,6 +10,24 @@
 namespace mesh {
 namespace ota {
 
+uint8_t* OtaManager::ensureSourceLeaves() {
+#if defined(ESP32_PLATFORM)
+  if (!_src_leaves) {
+    _src_leaves = static_cast<uint8_t*>(malloc(OTA_PROOFGEN_SCRATCH));
+  }
+#endif
+  return _src_leaves;
+}
+
+uint8_t* OtaManager::ensureScratch() {
+#if defined(ESP32_PLATFORM)
+  if (!_scratch) {
+    _scratch = static_cast<uint8_t*>(malloc(OTA_PROOFGEN_SCRATCH));
+  }
+#endif
+  return _scratch;
+}
+
 void OtaManager::begin(uint32_t my_target_id, OtaSend send, void* ctx) {
   _target = my_target_id; _send = send; _ctx = ctx;
   _fstate = IDLE; _have = 0; _fbc = 0;
@@ -24,10 +42,12 @@ void OtaManager::begin(uint32_t my_target_id, OtaSend send, void* ctx) {
 // we advertise / answer OTA_QUERY with) is the lightweight _serve[] registry.
 
 bool OtaManager::serve(const uint8_t* mota, uint32_t len) {
+  uint8_t* scratch = ensureScratch();
+  if (!scratch) return false;
   if (!mota_parse(mota, len, _view0.m)) return false;
   _view0.mfl = (uint16_t)(_view0.m.leaves - _view0.m.manifest_start);  // contiguous container
   _view0.read = nullptr; _view0.read_ctx = nullptr;                    // payload is contiguous _view0.m.payload
-  _view0.scratch = _scratch; _view0.scratch_sz = sizeof(_scratch);     // <=1024 blocks (RAM .mota is small)
+  _view0.scratch = scratch; _view0.scratch_sz = OTA_PROOFGEN_SCRATCH;  // <=1024 blocks (RAM .mota is small)
   _view0.valid = true;
   registerSelfEntry();
   return true;
@@ -52,12 +72,19 @@ bool OtaManager::serve_self(const uint8_t* manifest, uint16_t mfl, const uint8_t
 // (Re)build registry slot 0 from view0 (our own fw / RAM mota). Keeps any source entries in [1..].
 void OtaManager::registerSelfEntry() {
   if (!_view0.valid) return;
+  if (_n_serve > 0 && !_serve[0].is_self) {
+    if (_n_serve < OTA_MAX_SERVE) _n_serve++;
+    for (uint8_t i = _n_serve - 1; i > 0; i--) {
+      _serve[i] = _serve[i - 1];
+    }
+  } else if (_n_serve == 0) {
+    _n_serve = 1;
+  }
   ServeEntry& e = _serve[0];
   memcpy(e.mid, _view0.m.merkle_root, 4);
   e.target_id = _view0.m.target_id; e.fw_version = _view0.m.fw_version;
   e.codec_id = _view0.m.codec_id; e.flags = _view0.m.flags; e.have_count = _view0.m.block_count;
   e.is_self = true; e.src = nullptr; e.src_idx = 0;
-  if (_n_serve == 0) _n_serve = 1;
 }
 
 bool OtaManager::add_source(MotaSource* src) {
@@ -68,9 +95,8 @@ bool OtaManager::add_source(MotaSource* src) {
 }
 
 void OtaManager::refresh_sources() {
-  uint8_t base = _view0.valid ? 1 : 0;       // entry 0 stays our own fw
+  _n_serve = 0;
   if (_view0.valid) registerSelfEntry();
-  _n_serve = base;
   for (uint8_t s = 0; s < _n_src_obj; s++) {
     MotaSource* src = _src_list[s];
     if (!src) continue;
@@ -91,10 +117,20 @@ void OtaManager::refresh_sources() {
 
 void OtaManager::clear_sources() {
   _n_src_obj = 0; _srcv.valid = false;
-  _n_serve = _view0.valid ? 1 : 0;
+  _n_serve = 0;
   if (_view0.valid) registerSelfEntry();
 }
 
+void OtaManager::clear_primary() {
+  _view0.valid = false;
+  if (_n_serve > 0 && _serve[0].is_self) {
+    for (uint8_t i = 1; i < _n_serve; i++) {
+      _serve[i - 1] = _serve[i];
+    }
+    _n_serve--;
+  }
+}
+
 int OtaManager::serveEntryIndex(const uint8_t* mid) const {
   for (uint8_t i = 0; i < _n_serve; i++)
     if (memcmp(_serve[i].mid, mid, 4) == 0) return i;
@@ -119,21 +155,24 @@ bool OtaManager::loadSource(const ServeEntry& e) {
   if (!e.src) return false;
   uint16_t mfl = (uint16_t)(d.leaves_off - 8);
   if (mfl == 0 || mfl > sizeof(_src_manifest)) return false;
-  if (d.block_count == 0 || (uint64_t)d.block_count * 4 > sizeof(_src_leaves)) return false;
+  if (d.block_count == 0 || (uint64_t)d.block_count * 4 > OTA_PROOFGEN_SCRATCH) return false;
+  uint8_t* src_leaves = ensureSourceLeaves();
+  uint8_t* scratch = ensureScratch();
+  if (!src_leaves || !scratch) return false;
   bool ok = e.src->read(e.src_idx, 8, _src_manifest, mfl);
   if (!ok || !mota_parse_manifest(_src_manifest, mfl, _srcv.m)) return false;
   if (memcmp(_srcv.m.merkle_root, d.mid, 4) != 0) return false;       // descriptor/bytes disagree
   if (_srcv.m.block_count != d.block_count) return false;
-  ok = e.src->read(e.src_idx, d.leaves_off, _src_leaves, d.block_count * 4);
+  ok = e.src->read(e.src_idx, d.leaves_off, src_leaves, d.block_count * 4);
   if (!ok) return false;
   _srcv.m.manifest_start = _src_manifest;
-  _srcv.m.leaves   = _src_leaves;
+  _srcv.m.leaves   = src_leaves;
   _srcv.m.payload  = nullptr;
   _srcv.mfl = mfl;
   _srcv_rdctx.src = e.src; _srcv_rdctx.idx = e.src_idx;
   _srcv_rdctx.payload_off = d.payload_off;
   _srcv.read = srcReadTramp; _srcv.read_ctx = &_srcv_rdctx;
-  _srcv.scratch = _scratch; _srcv.scratch_sz = sizeof(_scratch);
+  _srcv.scratch = scratch; _srcv.scratch_sz = OTA_PROOFGEN_SCRATCH;
   memcpy(_srcv_mid, d.mid, 4);
   _srcv.valid = true;
   return true;
@@ -624,8 +663,9 @@ bool OtaManager::resumeStaged(const uint8_t* want_mid) {
   OTA_DBG("OTA: RESUME have=%u/%u total=%u\n", (unsigned)_have, (unsigned)bc, (unsigned)total);
 
   if (_have >= bc) {                                  // already complete -> verify root + finalize
-    if (bc * 4 <= sizeof(_scratch) && _fetch->read(_floff, _scratch, bc * 4)) {
-      uint8_t root[4]; merkle_root(root, _scratch, bc);
+    uint8_t* scratch = bc * 4 <= OTA_PROOFGEN_SCRATCH ? ensureScratch() : nullptr;
+    if (scratch && _fetch->read(_floff, scratch, bc * 4)) {
+      uint8_t root[4]; merkle_root(root, scratch, bc);
       _fstate = (memcmp(root, _froot, 4) == 0) ? COMPLETE : FAILED;
     } else {
       _fstate = COMPLETE;
@@ -701,8 +741,9 @@ void OtaManager::handleProof(const uint8_t* m, uint16_t n) {
   if (_checkpoint_blocks && _have % _checkpoint_blocks == 0) _fetch->checkpoint();
   if (_have < _fbc) { requestMissing(); return; }            // next block
   // all blocks present -> final root cross-check + finalize
-  if (_fbc * 4 <= sizeof(_scratch) && _fetch->read(_floff, _scratch, _fbc * 4)) {
-    uint8_t root[4]; merkle_root(root, _scratch, _fbc);
+  uint8_t* scratch = _fbc * 4 <= OTA_PROOFGEN_SCRATCH ? ensureScratch() : nullptr;
+  if (scratch && _fetch->read(_floff, scratch, _fbc * 4)) {
+    uint8_t root[4]; merkle_root(root, scratch, _fbc);
     _fstate = (memcmp(root, _froot, 4) == 0) ? COMPLETE : FAILED;
   } else {
     _fstate = COMPLETE;   // per-block proofs already guaranteed integrity vs the root
diff --git a/src/helpers/ota/OtaManager.h b/src/helpers/ota/OtaManager.h
index 7d4a966f..8028af0f 100644
--- a/src/helpers/ota/OtaManager.h
+++ b/src/helpers/ota/OtaManager.h
@@ -169,6 +169,9 @@ public:
   void refresh_sources();
   // Drop all external sources (keep serving our own fw).
   void clear_sources();
+  // Stop serving the primary caller-owned image while preserving attached sources.
+  // Call this before releasing or overwriting the primary image's backing buffer.
+  void clear_primary();
   uint8_t servedCount() const { return _n_serve; }   // total mOTAs we offer (own fw + folder)
   // Read-only view of one served entry (for `ota serve` listing): mid/target/fwver/codec/flags + is_self.
   const ServeEntry* servedEntry(uint8_t i) const { return i < _n_serve ? &_serve[i] : nullptr; }
@@ -337,8 +340,15 @@ private:
   MotaSource* _src_list[OTA_MAX_SOURCE_OBJ] = {nullptr};
   uint8_t     _n_src_obj = 0;
   uint8_t     _src_manifest[OTA_SRC_MANIFEST_MAX];   // manifest-minus-leaves of the loaded source mota
+#if defined(ESP32_PLATFORM)
+  // Folder-source leaves and proof scratch are cold-path working storage. Keep
+  // them off classic ESP32 .bss and allocate them on first use.
+  uint8_t*    _src_leaves = nullptr;
+  uint8_t*    _scratch = nullptr;
+#else
   uint8_t     _src_leaves[OTA_PROOFGEN_SCRATCH];     // leaves[] of the loaded source mota (<=1024 blocks)
   uint8_t     _scratch[OTA_PROOFGEN_SCRATCH];        // proof-gen / fetch root-check working buffer
+#endif
 
   // fetch
   OtaStore*  _fetch = nullptr;
@@ -386,6 +396,9 @@ private:
   bool       _diffing = false;                 // leaves are in; diffing the seed a batch per tick
   uint32_t   _diff_idx = 0;                    // next block index to diff against the seed
 
+  uint8_t* ensureSourceLeaves();
+  uint8_t* ensureScratch();
+
   // discovery: heard sources (beacon senders) + the catalog assembled from their OTA_HAVE replies
   struct Source { uint8_t seeder[4]; uint8_t digest[4]; uint8_t n_motas; uint32_t last_ms; bool have_catalog; };
   Source     _sources[OTA_MAX_SOURCES];
diff --git a/src/helpers/radiolib/RadioLibWrappers.cpp b/src/helpers/radiolib/RadioLibWrappers.cpp
index 3c8a105c..476f298b 100644
--- a/src/helpers/radiolib/RadioLibWrappers.cpp
+++ b/src/helpers/radiolib/RadioLibWrappers.cpp
@@ -704,25 +704,17 @@ float RadioLibWrapper::getLastSNR() const {
   return _radio->getSNR();
 }
 
-// Approximate SNR threshold per SF for successful reception (based on Semtech datasheets)
-static float snr_threshold[] = {
-    -7.5,  // SF7 needs at least -7.5 dB SNR
-    -10,   // SF8 needs at least -10 dB SNR
-    -12.5, // SF9 needs at least -12.5 dB SNR
-    -15,  // SF10 needs at least -15 dB SNR
-    -17.5,// SF11 needs at least -17.5 dB SNR
-    -20   // SF12 needs at least -20 dB SNR
-};
-
 float RadioLibWrapper::packetScoreInt(float snr, int sf, int packet_len) {
   if (sf < 7) return 0.0f;
-  
-  if (snr < snr_threshold[sf - 7]) return 0.0f;    // Below threshold, no chance of success
 
-  auto success_rate_based_on_snr = (snr - snr_threshold[sf - 7]) / 10.0;
-  auto collision_penalty = 1 - (packet_len / 256.0);   // Assuming max packet of 256 bytes
+  // Semtech's approximate threshold drops 2.5 dB for each step from SF7.
+  const float snr_threshold = -7.5f - (sf - 7) * 2.5f;
+  if (snr < snr_threshold) return 0.0f;
 
-  return max(0.0, min(1.0, success_rate_based_on_snr * collision_penalty));
+  const float success_rate = (snr - snr_threshold) * 0.1f;
+  const float collision_penalty = 1.0f - packet_len / 256.0f;
+  const float score = success_rate * collision_penalty;
+  return score < 1.0f ? score : 1.0f;
 }
 
 PacketMillis RadioLibWrapper::calcMaxPacketMillis(uint8_t sf, float bw, uint8_t cr, uint8_t preambleSymbols) {
diff --git a/test/test_ota/test_ota_core.cpp b/test/test_ota/test_ota_core.cpp
index 9f2d08ac..0358d0ce 100644
--- a/test/test_ota/test_ota_core.cpp
+++ b/test/test_ota/test_ota_core.cpp
@@ -530,6 +530,28 @@ private:
 };
 }
 
+TEST(OtaServe, ClearPrimaryInvalidatesCallerOwnedView) {
+  OtaManager manager;
+  manager.begin(0, nullptr, nullptr);
+
+  ASSERT_TRUE(manager.serve(SIM_MOTA, SIM_MOTA_LEN));
+  RamMotaSource folder;
+  folder.add(SIM_MOTA_1K, SIM_MOTA_1K_LEN);
+  ASSERT_TRUE(manager.add_source(&folder));
+  ASSERT_EQ(manager.servedCount(), 2);
+
+  manager.clear_primary();
+  ASSERT_EQ(manager.servedCount(), 1);
+  EXPECT_FALSE(manager.servedEntry(0)->is_self);
+
+  // A caller may release the container and later install a fresh primary view
+  // without dropping or overwriting attached folder sources.
+  EXPECT_TRUE(manager.serve(SIM_MOTA, SIM_MOTA_LEN));
+  ASSERT_EQ(manager.servedCount(), 2);
+  EXPECT_TRUE(manager.servedEntry(0)->is_self);
+  EXPECT_FALSE(manager.servedEntry(1)->is_self);
+}
+
 TEST(OtaTransfer, TwoManagersFullTransfer) {
   g_q.clear();
   OtaManager server, client;