diff --git a/modules/services/vehicle-stat-service/src/main/java/com/lingniu/ingest/vehiclestat/JdbcVehicleStatMetricRepository.java b/modules/services/vehicle-stat-service/src/main/java/com/lingniu/ingest/vehiclestat/JdbcVehicleStatMetricRepository.java
index 0fe7e5c3..818e6f6c 100644
--- a/modules/services/vehicle-stat-service/src/main/java/com/lingniu/ingest/vehiclestat/JdbcVehicleStatMetricRepository.java
+++ b/modules/services/vehicle-stat-service/src/main/java/com/lingniu/ingest/vehiclestat/JdbcVehicleStatMetricRepository.java
@@ -63,25 +63,26 @@ public final class JdbcVehicleStatMetricRepository implements VehicleStatReposit
         }
         String normalizedVin = clean(vin);
         Date date = Date.valueOf(statDate);
-        OptionalDouble existingStart = findMetric(normalizedVin, date, DAILY_MILEAGE_START_TOTAL_KEY);
-        double startTotalMileage = existingStart.orElse(totalMileageKm);
-        if (existingStart.isEmpty()) {
-            upsertMetric(normalizedVin, date, DAILY_MILEAGE_START_TOTAL_KEY, startTotalMileage,
-                    DAILY_MILEAGE_UNIT, DailyMileageStrategy.JT808_TOTAL_MILEAGE_DIFF.name());
-        }
-
-        OptionalDouble existingLatest = findMetric(normalizedVin, date, DAILY_MILEAGE_LATEST_TOTAL_KEY);
-        if (existingLatest.isPresent() && totalMileageKm < existingLatest.getAsDouble()) {
-            return findDailyStat(normalizedVin, statDate);
-        }
-        if (totalMileageKm < startTotalMileage) {
-            return findDailyStat(normalizedVin, statDate);
-        }
-
         String strategy = DailyMileageStrategy.JT808_TOTAL_MILEAGE_DIFF.name();
-        upsertMetric(normalizedVin, date, DAILY_MILEAGE_LATEST_TOTAL_KEY, totalMileageKm,
-                DAILY_MILEAGE_UNIT, strategy);
-        double dailyMileageKm = totalMileageKm - startTotalMileage;
+        OptionalDouble existingMin = findMetric(normalizedVin, date, DAILY_MILEAGE_START_TOTAL_KEY);
+        double minTotalMileage = existingMin.isPresent()
+                ? Math.min(existingMin.getAsDouble(), totalMileageKm)
+                : totalMileageKm;
+        if (existingMin.isEmpty() || Double.compare(minTotalMileage, existingMin.getAsDouble()) != 0) {
+            upsertMetric(normalizedVin, date, DAILY_MILEAGE_START_TOTAL_KEY, minTotalMileage,
+                    DAILY_MILEAGE_UNIT, strategy);
+        }
+
+        OptionalDouble existingMax = findMetric(normalizedVin, date, DAILY_MILEAGE_LATEST_TOTAL_KEY);
+        double maxTotalMileage = existingMax.isPresent()
+                ? Math.max(existingMax.getAsDouble(), totalMileageKm)
+                : totalMileageKm;
+        if (existingMax.isEmpty() || Double.compare(maxTotalMileage, existingMax.getAsDouble()) != 0) {
+            upsertMetric(normalizedVin, date, DAILY_MILEAGE_LATEST_TOTAL_KEY, maxTotalMileage,
+                    DAILY_MILEAGE_UNIT, strategy);
+        }
+
+        double dailyMileageKm = maxTotalMileage - minTotalMileage;
         VehicleDailyStatResult result = new VehicleDailyStatResult(
                 normalizedVin,
                 statDate,
diff --git a/modules/services/vehicle-stat-service/src/test/java/com/lingniu/ingest/vehiclestat/JdbcVehicleStatMetricRepositoryTest.java b/modules/services/vehicle-stat-service/src/test/java/com/lingniu/ingest/vehiclestat/JdbcVehicleStatMetricRepositoryTest.java
index e980ef15..e395b197 100644
--- a/modules/services/vehicle-stat-service/src/test/java/com/lingniu/ingest/vehiclestat/JdbcVehicleStatMetricRepositoryTest.java
+++ b/modules/services/vehicle-stat-service/src/test/java/com/lingniu/ingest/vehiclestat/JdbcVehicleStatMetricRepositoryTest.java
@@ -78,6 +78,39 @@ class JdbcVehicleStatMetricRepositoryTest {
                 String.class)).isEmpty();
     }
 
+    @Test
+    void recalculatesJt808MileageFromDailyMinAndMaxTotalsWhenSamplesArriveOutOfOrder() {
+        JdbcTemplate jdbcTemplate = new JdbcTemplate(new DriverManagerDataSource(
+                "jdbc:h2:mem:vehicle_stat_metric_jt808_out_of_order;MODE=MySQL;DATABASE_TO_LOWER=TRUE;DB_CLOSE_DELAY=-1",
+                "sa",
+                ""));
+        JdbcVehicleStatMetricRepository repository = new JdbcVehicleStatMetricRepository(jdbcTemplate);
+
+        repository.recordDailyMileageSample("VIN001", LocalDate.of(2026, 7, 1), 1008.75).orElseThrow();
+        VehicleDailyStatResult lowerSample = repository.recordDailyMileageSample(
+                "VIN001", LocalDate.of(2026, 7, 1), 1000.5).orElseThrow();
+        VehicleDailyStatResult higherSample = repository.recordDailyMileageSample(
+                "VIN001", LocalDate.of(2026, 7, 1), 1010.0).orElseThrow();
+
+        assertThat(lowerSample.dailyMileageKm()).hasValue(8.25);
+        assertThat(higherSample.dailyMileageKm()).hasValue(9.5);
+        assertThat(jdbcTemplate.queryForObject("""
+                SELECT metric_value
+                FROM vehicle_stat_metric
+                WHERE vin = 'VIN001' AND metric_key = 'daily_mileage_start_total_km'
+                """, Double.class)).isEqualTo(1000.5);
+        assertThat(jdbcTemplate.queryForObject("""
+                SELECT metric_value
+                FROM vehicle_stat_metric
+                WHERE vin = 'VIN001' AND metric_key = 'daily_mileage_latest_total_km'
+                """, Double.class)).isEqualTo(1010.0);
+        assertThat(jdbcTemplate.queryForObject("""
+                SELECT metric_value
+                FROM vehicle_stat_metric
+                WHERE vin = 'VIN001' AND metric_key = 'daily_mileage_km'
+                """, Double.class)).isEqualTo(9.5);
+    }
+
     @Test
     void readsLegacyCalculationMethodAsTotalMileageDifference() {
         JdbcTemplate jdbcTemplate = new JdbcTemplate(new DriverManagerDataSource(