diff --git a/libraries/AP_ESC_Telem/AP_ESC_Telem.cpp b/libraries/AP_ESC_Telem/AP_ESC_Telem.cpp
index f4ff9dea05a224..2b15c02f794fd3 100644
--- a/libraries/AP_ESC_Telem/AP_ESC_Telem.cpp
+++ b/libraries/AP_ESC_Telem/AP_ESC_Telem.cpp
@@ -104,15 +104,12 @@ uint8_t AP_ESC_Telem::get_motor_frequencies_hz(uint8_t nfreqs, float* freqs) con
 // ESC_TELEM_DATA_TIMEOUT_MS/ESC_RPM_DATA_TIMEOUT_US
 uint32_t AP_ESC_Telem::get_active_esc_mask() const {
     uint32_t ret = 0;
-    const uint32_t now = AP_HAL::millis();
-    uint32_t now_us = AP_HAL::micros();
     for (uint8_t i = 0; i < ESC_TELEM_MAX_ESCS; i++) {
         if (_telem_data[i].last_update_ms == 0 && !was_rpm_data_ever_reported(_rpm_data[i])) {
             // have never seen telem from this ESC
             continue;
         }
-        if (_telem_data[i].stale(now)
-            && !rpm_data_within_timeout(_rpm_data[i], now_us, ESC_RPM_DATA_TIMEOUT_US)) {
+        if (_telem_data[i].stale() && !_rpm_data[i].data_valid) {
             continue;
         }
         ret |= (1U << i);
@@ -125,15 +122,12 @@ uint8_t AP_ESC_Telem::get_max_rpm_esc() const
 {
     uint32_t ret = 0;
     float max_rpm = 0;
-    const uint32_t now = AP_HAL::millis();
-    const uint32_t now_us = AP_HAL::micros();
     for (uint8_t i = 0; i < ESC_TELEM_MAX_ESCS; i++) {
         if (_telem_data[i].last_update_ms == 0 && !was_rpm_data_ever_reported(_rpm_data[i])) {
             // have never seen telem from this ESC
             continue;
         }
-        if (_telem_data[i].stale(now)
-            && !rpm_data_within_timeout(_rpm_data[i], now_us, ESC_RPM_DATA_TIMEOUT_US)) {
+        if (_telem_data[i].stale() && !_rpm_data[i].data_valid) {
             continue;
         }
         if (_rpm_data[i].rpm > max_rpm) {
@@ -153,13 +147,12 @@ uint8_t AP_ESC_Telem::get_num_active_escs() const {
 // return the whether all the motors in servo_channel_mask are running
 bool AP_ESC_Telem::are_motors_running(uint32_t servo_channel_mask, float min_rpm, float max_rpm) const
 {
-    const uint32_t now = AP_HAL::micros();
 
     for (uint8_t i = 0; i < ESC_TELEM_MAX_ESCS; i++) {
         if (BIT_IS_SET(servo_channel_mask, i)) {
             const volatile AP_ESC_Telem_Backend::RpmData& rpmdata = _rpm_data[i];
             // we choose a relatively strict measure of health so that failsafe actions can rely on the results
-            if (!rpm_data_within_timeout(rpmdata, now, ESC_RPM_CHECK_TIMEOUT_US)) {
+            if (!rpm_data_within_timeout(rpmdata, ESC_RPM_CHECK_TIMEOUT_US)) {
                 return false;
             }
             if (rpmdata.rpm < min_rpm) {
@@ -201,7 +194,7 @@ bool AP_ESC_Telem::get_rpm(uint8_t esc_index, float& rpm) const
     }
 
     const uint32_t now = AP_HAL::micros();
-    if (rpm_data_within_timeout(rpmdata, now, ESC_RPM_DATA_TIMEOUT_US)) {
+    if (rpmdata.data_valid) {
         const float slew = MIN(1.0f, (now - rpmdata.last_update_us) * rpmdata.update_rate_hz * (1.0f / 1e6f));
         rpm = (rpmdata.prev_rpm + (rpmdata.rpm - rpmdata.prev_rpm) * slew);
 
@@ -225,9 +218,7 @@ bool AP_ESC_Telem::get_raw_rpm(uint8_t esc_index, float& rpm) const
 
     const volatile AP_ESC_Telem_Backend::RpmData& rpmdata = _rpm_data[esc_index];
 
-    const uint32_t now = AP_HAL::micros();
-
-    if (!rpm_data_within_timeout(rpmdata, now, ESC_RPM_DATA_TIMEOUT_US)) {
+    if (!rpmdata.data_valid) {
         return false;
     }
 
@@ -412,9 +403,6 @@ void AP_ESC_Telem::send_esc_telemetry_mavlink(uint8_t mav_chan)
         return;
     }
 
-    const uint32_t now = AP_HAL::millis();
-    const uint32_t now_us = AP_HAL::micros();
-
     // loop through groups of 4 ESCs
     const uint8_t esc_offset = constrain_int16(mavlink_offset, 0, ESC_TELEM_MAX_ESCS-1);
 
@@ -435,8 +423,7 @@ void AP_ESC_Telem::send_esc_telemetry_mavlink(uint8_t mav_chan)
         for (uint8_t j=0; j<4; j++) {
             const uint8_t esc_id = (i * 4 + j) + esc_offset;
             if (esc_id < ESC_TELEM_MAX_ESCS &&
-                (!_telem_data[esc_id].stale(now) ||
-                 rpm_data_within_timeout(_rpm_data[esc_id], now_us, ESC_RPM_DATA_TIMEOUT_US))) {
+                (!_telem_data[esc_id].stale() || _rpm_data[esc_id].data_valid)) {
                 all_stale = false;
                 break;
             }
@@ -593,6 +580,7 @@ void AP_ESC_Telem::update_telem_data(const uint8_t esc_index, const AP_ESC_Telem
     telemdata.count++;
     telemdata.types |= data_mask;
     telemdata.last_update_ms = AP_HAL::millis();
+    telemdata.any_data_valid = true;
 }
 
 // record an update to the RPM together with timestamp, this allows the notch values to be slewed
@@ -808,23 +796,37 @@ void AP_ESC_Telem::update()
     }
 #endif  // HAL_LOGGING_ENABLED
 
-    const uint32_t now_us = AP_HAL::micros();
     for (uint8_t i = 0; i < ESC_TELEM_MAX_ESCS; i++) {
+        // copy the last_updated_us timestamp to avoid any race issues
+        const uint32_t last_updated_us = _rpm_data[i].last_update_us;
+        const uint32_t now_us = AP_HAL::micros();
         // Invalidate RPM data if not received for too long
-        if ((now_us - _rpm_data[i].last_update_us) > ESC_RPM_DATA_TIMEOUT_US) {
+        if (AP_HAL::timeout_expired(last_updated_us, now_us, ESC_RPM_DATA_TIMEOUT_US)) {
             _rpm_data[i].data_valid = false;
         }
+        const uint32_t last_telem_data_ms = _telem_data[i].last_update_ms;
+        const uint32_t now_ms = AP_HAL::millis();
+        // Invalidate telemetry data if not received for too long
+        if (AP_HAL::timeout_expired(last_telem_data_ms, now_ms, ESC_TELEM_DATA_TIMEOUT_MS)) {
+            _telem_data[i].any_data_valid = false;
+        }
     }
 }
 
-bool AP_ESC_Telem::rpm_data_within_timeout(const volatile AP_ESC_Telem_Backend::RpmData &instance, const uint32_t now_us, const uint32_t timeout_us)
+// NOTE: This function should only be used to check timeouts other than 
+// ESC_RPM_DATA_TIMEOUT_US. Timeouts equal to ESC_RPM_DATA_TIMEOUT_US should
+// use RpmData::data_valid, which is cheaper and achieves the same result.
+bool AP_ESC_Telem::rpm_data_within_timeout(const volatile AP_ESC_Telem_Backend::RpmData &instance, const uint32_t timeout_us)
 {
+    // copy the last_update_us timestamp to avoid any race issues
+    const uint32_t last_update_us = instance.last_update_us;
+    const uint32_t now_us = AP_HAL::micros();
     // easy case, has the time window been crossed so it's invalid
-    if ((now_us - instance.last_update_us) > timeout_us) {
+    if (AP_HAL::timeout_expired(last_update_us, now_us, timeout_us)) {
         return false;
     }
     // we never got a valid data, to it's invalid
-    if (instance.last_update_us == 0) {
+    if (last_update_us == 0) {
         return false;
     }
     // check if things generally expired on us, this is done to handle time wrapping
diff --git a/libraries/AP_ESC_Telem/AP_ESC_Telem.h b/libraries/AP_ESC_Telem/AP_ESC_Telem.h
index cf4a5a9cc2d573..7b39646b160324 100644
--- a/libraries/AP_ESC_Telem/AP_ESC_Telem.h
+++ b/libraries/AP_ESC_Telem/AP_ESC_Telem.h
@@ -134,7 +134,7 @@ class AP_ESC_Telem {
 private:
 
     // helper that validates RPM data
-    static bool rpm_data_within_timeout (const volatile AP_ESC_Telem_Backend::RpmData &instance, const uint32_t now_us, const uint32_t timeout_us);
+    static bool rpm_data_within_timeout (const volatile AP_ESC_Telem_Backend::RpmData &instance, const uint32_t timeout_us);
     static bool was_rpm_data_ever_reported (const volatile AP_ESC_Telem_Backend::RpmData &instance);
 
 #if AP_EXTENDED_DSHOT_TELEM_V2_ENABLED
diff --git a/libraries/AP_ESC_Telem/AP_ESC_Telem_Backend.cpp b/libraries/AP_ESC_Telem/AP_ESC_Telem_Backend.cpp
index a63c0191c5c853..a197f6bdc1287d 100644
--- a/libraries/AP_ESC_Telem/AP_ESC_Telem_Backend.cpp
+++ b/libraries/AP_ESC_Telem/AP_ESC_Telem_Backend.cpp
@@ -48,9 +48,9 @@ void AP_ESC_Telem_Backend::update_telem_data(const uint8_t esc_index, const Tele
 /*
   return true if the data is stale
  */
-bool AP_ESC_Telem_Backend::TelemetryData::stale(uint32_t now_ms) const volatile
+bool AP_ESC_Telem_Backend::TelemetryData::stale() const volatile
 {
-    return last_update_ms == 0 || now_ms - last_update_ms > ESC_TELEM_DATA_TIMEOUT_MS;
+    return last_update_ms == 0 || !any_data_valid;
 }
 
 /*
@@ -62,7 +62,7 @@ bool AP_ESC_Telem_Backend::TelemetryData::valid(const uint16_t type_mask) const
         // Requested type not available
         return false;
     }
-    return !stale(AP_HAL::millis());
+    return !stale();
 }
 
 #endif
diff --git a/libraries/AP_ESC_Telem/AP_ESC_Telem_Backend.h b/libraries/AP_ESC_Telem/AP_ESC_Telem_Backend.h
index f127c0d71ab92c..b41dc48519e879 100644
--- a/libraries/AP_ESC_Telem/AP_ESC_Telem_Backend.h
+++ b/libraries/AP_ESC_Telem/AP_ESC_Telem_Backend.h
@@ -30,8 +30,11 @@ class AP_ESC_Telem_Backend {
         uint8_t power_percentage;   // Percentage of output power
 #endif // AP_EXTENDED_ESC_TELEM_ENABLED
 
+        // set to false if no data has been received within the timeout period
+        bool any_data_valid;
+
         // return true if the data is stale
-        bool stale(uint32_t now_ms) const volatile;
+        bool stale() const volatile;
 
         //  return true if the requested type of data is available and not stale
         bool valid(const uint16_t type_mask) const volatile;
diff --git a/libraries/AP_Vehicle/AP_Vehicle.cpp b/libraries/AP_Vehicle/AP_Vehicle.cpp
index b4f002d52e6fab..7436fd1da87fc6 100644
--- a/libraries/AP_Vehicle/AP_Vehicle.cpp
+++ b/libraries/AP_Vehicle/AP_Vehicle.cpp
@@ -624,6 +624,8 @@ const AP_Scheduler::Task AP_Vehicle::scheduler_tasks[] = {
 #endif
     SCHED_TASK(send_watchdog_reset_statustext,         0.1,     20, 225),
 #if HAL_WITH_ESC_TELEM
+    // This update function is responsible for checking timeouts and invalidating the ESC telemetry data.
+    // Be mindful of this if you are planning to reduce the frequency from 100Hz.
     SCHED_TASK_CLASS(AP_ESC_Telem, &vehicle.esc_telem,      update,                  100,  50, 230),
 #endif
 #if AP_SERVO_TELEM_ENABLED