diff --git a/test/aprsme_web/live/map_live/historical_loader_test.exs b/test/aprsme_web/live/map_live/historical_loader_test.exs
index 69c68b6..811f140 100644
--- a/test/aprsme_web/live/map_live/historical_loader_test.exs
+++ b/test/aprsme_web/live/map_live/historical_loader_test.exs
@@ -219,4 +219,115 @@ defmodule AprsmeWeb.MapLive.HistoricalLoaderTest do
       refute result.assigns.historical_loading
     end
   end
+
+  describe "advance cursor path via packets with id/received_at" do
+    test "advances cursor when last packet has both id and received_at" do
+      now = DateTime.utc_now()
+
+      Mox.stub(Aprsme.PacketsMock, :get_recent_packets, fn _opts ->
+        [
+          %{
+            id: "cursor-test-1",
+            sender: "CUR1",
+            base_callsign: "CUR1",
+            ssid: "1",
+            lat: 33.5,
+            lon: -96.5,
+            has_position: true,
+            symbol_table_id: "/",
+            symbol_code: ">",
+            received_at: now,
+            path: ""
+          }
+        ]
+      end)
+
+      socket =
+        build_socket(%{
+          map_bounds: %{north: 34.0, south: 32.0, east: -95.0, west: -97.0},
+          map_zoom: 10,
+          historical_loading: true,
+          loading_generation: 1
+        })
+
+      result = HistoricalLoader.load_historical_batch(socket, 0, nil)
+      # Cursor should be set from last packet.
+      assert result.assigns.historical_cursor == %{received_at: now, id: "cursor-test-1"}
+    end
+  end
+
+  describe "loading with invalid-coord packets filters them out" do
+    test "invalid coordinates don't break the pipeline" do
+      now = DateTime.utc_now()
+
+      Mox.stub(Aprsme.PacketsMock, :get_recent_packets, fn _opts ->
+        [
+          %{
+            id: "bad-coord",
+            sender: "BAD1",
+            base_callsign: "BAD1",
+            ssid: "1",
+            # Out-of-range coordinates — should be filtered.
+            lat: 200.0,
+            lon: 500.0,
+            has_position: true,
+            symbol_table_id: "/",
+            symbol_code: ">",
+            received_at: now,
+            path: ""
+          }
+        ]
+      end)
+
+      socket =
+        build_socket(%{
+          map_bounds: %{north: 34.0, south: 32.0, east: -95.0, west: -97.0},
+          map_zoom: 10,
+          historical_loading: true,
+          loading_generation: 1
+        })
+
+      result = HistoricalLoader.load_historical_batch(socket, 0, nil)
+      # Still advanced loading state even when all packets were filtered.
+      assert is_map(result.assigns)
+    end
+  end
+
+  describe "zoom >= 10 single-batch branch" do
+    test "starts loading in a single batch at high zoom" do
+      Mox.stub(Aprsme.PacketsMock, :get_recent_packets, fn _opts -> [] end)
+
+      socket =
+        build_socket(%{
+          map_bounds: %{north: 34.0, south: 32.0, east: -95.0, west: -97.0},
+          map_zoom: 12,
+          loading_generation: 0
+        })
+
+      result = HistoricalLoader.start_progressive_historical_loading(socket)
+
+      # High zoom → total_batches set to 1 for single-batch path.
+      assert result.assigns.total_batches == 1
+      assert result.assigns.loading_generation == 1
+    end
+  end
+
+  describe "max packets-for-zoom limit" do
+    test "finishes loading when batch_offset * batch_size exceeds zoom limit" do
+      # At zoom 10, limit=1500, batch_size=500. A batch_offset of 3 exceeds
+      # the 1500-row zoom limit, so the load should finish without a query.
+      socket =
+        build_socket(%{
+          map_bounds: %{north: 34.0, south: 32.0, east: -95.0, west: -97.0},
+          map_zoom: 10,
+          historical_loading: true,
+          total_batches: 4,
+          loading_generation: 1
+        })
+
+      result = HistoricalLoader.load_historical_batch(socket, 3, nil)
+      # finish_historical_loading flips historical_loading off.
+      refute result.assigns.historical_loading
+    end
+  end
 end