diff --git a/ordinis-rest-api/src/main/java/cloud/nstart/terravault/ordinis/restapi/service/SnapshotsService.java b/ordinis-rest-api/src/main/java/cloud/nstart/terravault/ordinis/restapi/service/SnapshotsService.java
index d6b9ae1..45df50f 100644
--- a/ordinis-rest-api/src/main/java/cloud/nstart/terravault/ordinis/restapi/service/SnapshotsService.java
+++ b/ordinis-rest-api/src/main/java/cloud/nstart/terravault/ordinis/restapi/service/SnapshotsService.java
@@ -88,7 +88,11 @@ public class SnapshotsService {
     boolean currentMarked = false;
     DateTimeFormatter fmt = "hour".equals(gran) ? RU_HOUR : RU_DAY;
     for (Object[] row : rows) {
-      OffsetDateTime bucket = ((java.sql.Timestamp) row[0]).toInstant().atOffset(now.getOffset());
+      // pgJDBC 42.7+ возвращает timestamptz как java.time.Instant вместо
+      // java.sql.Timestamp (как было в 42.6). Native query тип определяется
+      // в runtime — поддерживаем оба + OffsetDateTime для completeness.
+      // Без этой branch'и был ClassCastException 500 на каждом запросе.
+      OffsetDateTime bucket = toBucketOffsetDateTime(row[0], now);
       long changedSinceLast = ((Number) row[1]).longValue();
       boolean isCurrent = !currentMarked && !bucket.isAfter(now);
       if (isCurrent) currentMarked = true;
@@ -103,6 +107,38 @@ public class SnapshotsService {
     return new SnapshotsResponse(d.getName(), windowFrom, windowTo, snapshots);
   }
 
+  /**
+   * Convert native-query Object[] timestamp column → OffsetDateTime.
+   *
+   * <p>Postgres JDBC driver returns timestamptz columns в разных форматах
+   * в зависимости от версии:
+   * <ul>
+   *   <li>42.6 и старше — {@link java.sql.Timestamp}</li>
+   *   <li>42.7+ (current) — {@link java.time.Instant}</li>
+   *   <li>при {@code jdbc.timestamp.return-type=offset-date-time} —
+   *       {@link OffsetDateTime} напрямую</li>
+   * </ul>
+   *
+   * <p>Native query через {@code @Query(nativeQuery = true)} возвращает Object[]
+   * без compile-time типа — поддерживаем все три варианта. Иначе CCE на runtime.
+   */
+  static OffsetDateTime toBucketOffsetDateTime(Object raw, OffsetDateTime now) {
+    if (raw == null) {
+      throw new IllegalStateException("bucket timestamp is null in result row");
+    }
+    if (raw instanceof java.sql.Timestamp ts) {
+      return ts.toInstant().atOffset(now.getOffset());
+    }
+    if (raw instanceof java.time.Instant inst) {
+      return inst.atOffset(now.getOffset());
+    }
+    if (raw instanceof OffsetDateTime odt) {
+      return odt.withOffsetSameInstant(now.getOffset());
+    }
+    throw new IllegalStateException(
+        "Unexpected timestamp type from native query: " + raw.getClass().getName());
+  }
+
   // === DTOs ===
 
   public record Snapshot(
diff --git a/ordinis-rest-api/src/test/java/cloud/nstart/terravault/ordinis/restapi/service/SnapshotsServiceTest.java b/ordinis-rest-api/src/test/java/cloud/nstart/terravault/ordinis/restapi/service/SnapshotsServiceTest.java
index 3335fdd..95440ca 100644
--- a/ordinis-rest-api/src/test/java/cloud/nstart/terravault/ordinis/restapi/service/SnapshotsServiceTest.java
+++ b/ordinis-rest-api/src/test/java/cloud/nstart/terravault/ordinis/restapi/service/SnapshotsServiceTest.java
@@ -112,6 +112,63 @@ class SnapshotsServiceTest {
     assertThat(result.snapshots().get(1).changedSinceLast()).isEqualTo(5L);
   }
 
+  /**
+   * Регрессия prod-bug 2026-05-19: pgJDBC 42.7+ возвращает timestamptz как
+   * {@link java.time.Instant} вместо {@code java.sql.Timestamp}. Старый код
+   * жёстко кастил в Timestamp → ClassCastException на каждом запросе.
+   *
+   * <p>Тест проверяет что service корректно мапит Instant в OffsetDateTime.
+   */
+  @Test
+  void snapshots_acceptsInstantFromPg42_7Driver() {
+    var d = def("dict", DataScope.PUBLIC);
+    when(defRepo.findByName("dict")).thenReturn(Optional.of(d));
+    java.time.Instant april = OffsetDateTime.parse("2026-04-01T00:00:00Z").toInstant();
+    java.time.Instant may = OffsetDateTime.parse("2026-05-11T00:00:00Z").toInstant();
+    when(recRepo.findSnapshotBuckets(eq(d.getId()), anyString(), any(), any(), eq("day")))
+        .thenReturn(List.<Object[]>of(
+            new Object[]{may, 5L},
+            new Object[]{april, 3L}));
+
+    var result = service.findSnapshots("dict", null, null, "day");
+
+    assertThat(result.snapshots()).hasSize(2);
+    assertThat(result.snapshots().get(0).changedSinceLast()).isEqualTo(3L);
+    assertThat(result.snapshots().get(1).changedSinceLast()).isEqualTo(5L);
+  }
+
+  /**
+   * Defensive coverage: если configurable
+   * {@code pgjdbc.timestamp.return-type=offset-date-time} в будущем включат,
+   * helper должен handle и OffsetDateTime. (Сейчас не активно, но проверяем
+   * чтобы не сломаться при future driver tuning.)
+   */
+  @Test
+  void snapshots_acceptsOffsetDateTime() {
+    var d = def("dict", DataScope.PUBLIC);
+    when(defRepo.findByName("dict")).thenReturn(Optional.of(d));
+    OffsetDateTime apr = OffsetDateTime.parse("2026-04-01T00:00:00Z");
+    when(recRepo.findSnapshotBuckets(any(), anyString(), any(), any(), anyString()))
+        .thenReturn(List.<Object[]>of(new Object[]{apr, 1L}));
+
+    var result = service.findSnapshots("dict", null, null, "day");
+
+    assertThat(result.snapshots()).hasSize(1);
+    assertThat(result.snapshots().get(0).changedSinceLast()).isEqualTo(1L);
+  }
+
+  @Test
+  void snapshots_rejectsUnexpectedTimestampType() {
+    var d = def("dict", DataScope.PUBLIC);
+    when(defRepo.findByName("dict")).thenReturn(Optional.of(d));
+    when(recRepo.findSnapshotBuckets(any(), anyString(), any(), any(), anyString()))
+        .thenReturn(List.<Object[]>of(new Object[]{"2026-04-01", 1L}));
+
+    assertThatThrownBy(() -> service.findSnapshots("dict", null, null, "day"))
+        .isInstanceOf(IllegalStateException.class)
+        .hasMessageContaining("Unexpected timestamp type");
+  }
+
   @Test
   void snapshots_currentMarkedOnce_evenWithFutureBuckets() {
     var d = def("dict", DataScope.PUBLIC);