graph/db: use exclusive end time for horizon queries per BOLT 07

diff --git a/graph/db/graph.go b/graph/db/graph.go
index 507312f..6b29bfc 100644
--- a/graph/db/graph.go
+++ b/graph/db/graph.go
@@ -721,8 +721,8 @@ func (c *ChannelGraph) ForEachNodeCacheable(ctx context.Context,
 	return c.db.ForEachNodeCacheable(ctx, v, cb, reset)
 }
 
-// NodeUpdatesInHorizon returns all known lightning nodes with updates in the
-// range.
+// NodeUpdatesInHorizon returns all known lightning nodes with an update
+// timestamp in [startTime, endTime) per BOLT 07.
 func (c *ChannelGraph) NodeUpdatesInHorizon(ctx context.Context,
 	startTime, endTime time.Time,
 	opts ...IteratorOption) iter.Seq2[*models.Node, error] {
@@ -783,8 +783,8 @@ func (c *ChannelGraph) HighestChanID(ctx context.Context,
 	return c.db.HighestChanID(ctx, v)
 }
 
-// ChanUpdatesInHorizon returns all known channel edges with updates in the
-// horizon.
+// ChanUpdatesInHorizon returns all known channel edges with at least one
+// policy update timestamp in [startTime, endTime) per BOLT 07.
 func (c *ChannelGraph) ChanUpdatesInHorizon(ctx context.Context,
 	startTime, endTime time.Time,
 	opts ...IteratorOption) iter.Seq2[ChannelEdge, error] {
@@ -944,8 +944,8 @@ func (c *VersionedGraph) NumZombies(ctx context.Context) (uint64, error) {
 	return c.db.NumZombies(ctx, c.v)
 }
 
-// NodeUpdatesInHorizon returns all known lightning nodes which have an update
-// timestamp within the passed range.
+// NodeUpdatesInHorizon returns all known lightning nodes with an update
+// timestamp in [startTime, endTime) per BOLT 07.
 func (c *VersionedGraph) NodeUpdatesInHorizon(ctx context.Context,
 	startTime, endTime time.Time,
 	opts ...IteratorOption) iter.Seq2[*models.Node, error] {
diff --git a/graph/db/graph_test.go b/graph/db/graph_test.go
index acd548d..7f1d3b4 100644
--- a/graph/db/graph_test.go
+++ b/graph/db/graph_test.go
@@ -2708,12 +2708,15 @@ func testNodeUpdatesWithBatchSize(t *testing.T, ctx context.Context,
 			end:   startTime.Add(26 * time.Hour),
 			want:  25,
 		},
+		// The end time is exclusive per BOLT 07, so we
+		// add one extra hour to include the last node in
+		// the desired range.
 		{
 			name:  "first batch only",
 			start: startTime,
 			end: startTime.Add(
 				time.Duration(
-					min(batchSize, 25)-1,
+					min(batchSize, 25),
 				) * time.Hour,
 			),
 			want: min(batchSize, 25),
@@ -2723,7 +2726,7 @@ func testNodeUpdatesWithBatchSize(t *testing.T, ctx context.Context,
 			start: startTime,
 			end: startTime.Add(
 				time.Duration(
-					min(batchSize, 24),
+					min(batchSize+1, 25),
 				) * time.Hour,
 			),
 			want: min(batchSize+1, 25),
@@ -2748,16 +2751,19 @@ func testNodeUpdatesWithBatchSize(t *testing.T, ctx context.Context,
 				)
 			}(),
 			end: func() time.Time {
+				// End is exclusive, so we add
+				// one hour to include the node
+				// at exactly the start time.
 				if batchSize <= 25 {
 					return startTime.Add(
 						time.Duration(
-							batchSize-1,
+							batchSize,
 						) * time.Hour,
 					)
 				}
 
 				return startTime.Add(
-					time.Duration(25) * time.Hour,
+					time.Duration(26) * time.Hour,
 				)
 			}(),
 			want: func() int {
@@ -2964,6 +2970,177 @@ func TestChanUpdatesInHorizonBoundaryConditions(t *testing.T) {
 	}
 }
 
+// TestNodeUpdatesInHorizonExclusiveEnd verifies that NodeUpdatesInHorizon uses
+// an exclusive end time per BOLT 07: "timestamp is greater or equal to
+// first_timestamp, and less than first_timestamp plus timestamp_range".
+func TestNodeUpdatesInHorizonExclusiveEnd(t *testing.T) {
+	t.Parallel()
+	ctx := t.Context()
+
+	graph := MakeTestGraph(t)
+
+	// Create three nodes at timestamps 100, 200, and 300.
+	timestamps := []int64{100, 200, 300}
+	for _, ts := range timestamps {
+		node := createTestVertex(t, lnwire.GossipVersion1)
+		node.LastUpdate = time.Unix(ts, 0)
+		require.NoError(t, graph.AddNode(ctx, node))
+	}
+
+	tests := []struct {
+		name  string
+		start time.Time
+		end   time.Time
+		want  int
+	}{
+		{
+			// Start is inclusive: node at exactly startTime
+			// should be included.
+			name:  "start time is inclusive",
+			start: time.Unix(100, 0),
+			end:   time.Unix(101, 0),
+			want:  1,
+		},
+		{
+			// End is exclusive: node at exactly endTime should
+			// NOT be included.
+			name:  "end time is exclusive",
+			start: time.Unix(100, 0),
+			end:   time.Unix(200, 0),
+			want:  1,
+		},
+		{
+			// One second past the boundary includes the node.
+			name:  "one past end includes boundary node",
+			start: time.Unix(100, 0),
+			end:   time.Unix(201, 0),
+			want:  2,
+		},
+		{
+			// Range [200, 300) should include node at 200 but
+			// not node at 300.
+			name:  "mid range excludes end",
+			start: time.Unix(200, 0),
+			end:   time.Unix(300, 0),
+			want:  1,
+		},
+		{
+			// Range [200, 301) should include nodes at 200
+			// and 300.
+			name:  "mid range includes end plus one",
+			start: time.Unix(200, 0),
+			end:   time.Unix(301, 0),
+			want:  2,
+		},
+	}
+
+	for _, tc := range tests {
+		t.Run(tc.name, func(t *testing.T) {
+			iter := graph.NodeUpdatesInHorizon(
+				ctx, tc.start, tc.end,
+			)
+
+			nodes, err := fn.CollectErr(iter)
+			require.NoError(t, err)
+			require.Len(t, nodes, tc.want)
+		})
+	}
+}
+
+// TestChanUpdatesInHorizonExclusiveEnd verifies that ChanUpdatesInHorizon uses
+// an exclusive end time per BOLT 07: "timestamp is greater or equal to
+// first_timestamp, and less than first_timestamp plus timestamp_range".
+func TestChanUpdatesInHorizonExclusiveEnd(t *testing.T) {
+	t.Parallel()
+	ctx := t.Context()
+
+	graph := MakeTestGraph(t)
+
+	node1 := createTestVertex(t, lnwire.GossipVersion1)
+	node2 := createTestVertex(t, lnwire.GossipVersion1)
+	require.NoError(t, graph.AddNode(ctx, node1))
+	require.NoError(t, graph.AddNode(ctx, node2))
+
+	// Create three channels with policy updates at timestamps 100, 200,
+	// and 300.
+	timestamps := []int64{100, 200, 300}
+	for i, ts := range timestamps {
+		channel, chanID := createEdge(
+			lnwire.GossipVersion1, uint32(i*10), 0, 0, 0,
+			node1, node2,
+		)
+		require.NoError(t, graph.AddChannelEdge(ctx, channel))
+
+		edge := newEdgePolicy(
+			lnwire.GossipVersion1, chanID.ToUint64(), ts, true,
+		)
+		edge.ChannelFlags = 0
+		edge.ToNode = node2.PubKeyBytes
+		edge.SigBytes = testSig.Serialize()
+		require.NoError(t, graph.UpdateEdgePolicy(ctx, edge))
+	}
+
+	tests := []struct {
+		name  string
+		start time.Time
+		end   time.Time
+		want  int
+	}{
+		{
+			// Start is inclusive: channel at exactly startTime
+			// should be included.
+			name:  "start time is inclusive",
+			start: time.Unix(100, 0),
+			end:   time.Unix(101, 0),
+			want:  1,
+		},
+		{
+			// End is exclusive: channel at exactly endTime
+			// should NOT be included.
+			name:  "end time is exclusive",
+			start: time.Unix(100, 0),
+			end:   time.Unix(200, 0),
+			want:  1,
+		},
+		{
+			// One second past the boundary includes the
+			// channel.
+			name:  "one past end includes boundary channel",
+			start: time.Unix(100, 0),
+			end:   time.Unix(201, 0),
+			want:  2,
+		},
+		{
+			// Range [200, 300) should include channel at 200
+			// but not channel at 300.
+			name:  "mid range excludes end",
+			start: time.Unix(200, 0),
+			end:   time.Unix(300, 0),
+			want:  1,
+		},
+		{
+			// Range [200, 301) should include channels at 200
+			// and 300.
+			name:  "mid range includes end plus one",
+			start: time.Unix(200, 0),
+			end:   time.Unix(301, 0),
+			want:  2,
+		},
+	}
+
+	for _, tc := range tests {
+		t.Run(tc.name, func(t *testing.T) {
+			iter := graph.ChanUpdatesInHorizon(
+				ctx, tc.start, tc.end,
+			)
+
+			channels, err := fn.CollectErr(iter)
+			require.NoError(t, err)
+			require.Len(t, channels, tc.want)
+		})
+	}
+}
+
 // TestFilterKnownChanIDsZombieRevival tests that if a ChannelUpdateInfo is
 // passed to FilterKnownChanIDs that contains a channel that we have marked as
 // a zombie, then we will mark it as live again if the new ChannelUpdate has
diff --git a/graph/db/interfaces.go b/graph/db/interfaces.go
index a725cb8..2c9d5f5 100644
--- a/graph/db/interfaces.go
+++ b/graph/db/interfaces.go
@@ -120,10 +120,11 @@ type Store interface { //nolint:interfacebloat
 	DeleteNode(ctx context.Context, v lnwire.GossipVersion,
 		nodePub route.Vertex) error
 
-	// NodeUpdatesInHorizon returns all the known lightning node which have
-	// an update timestamp within the passed range. This method can be used
-	// by two nodes to quickly determine if they have the same set of up to
-	// date node announcements.
+	// NodeUpdatesInHorizon returns all the known lightning nodes which have
+	// an update timestamp greater than or equal to startTime and less than
+	// endTime, i.e. the range [startTime, endTime) per BOLT 07. This
+	// method can be used by two nodes to quickly determine if they have
+	// the same set of up to date node announcements.
 	NodeUpdatesInHorizon(ctx context.Context, startTime, endTime time.Time,
 		opts ...IteratorOption) iter.Seq2[*models.Node, error]
 
@@ -256,8 +257,9 @@ type Store interface { //nolint:interfacebloat
 		uint64, error)
 
 	// ChanUpdatesInHorizon returns all the known channel edges which have
-	// at least one edge that has an update timestamp within the specified
-	// horizon.
+	// at least one edge that has an update timestamp greater than or equal
+	// to startTime and less than endTime, i.e. the range
+	// [startTime, endTime) per BOLT 07.
 	ChanUpdatesInHorizon(ctx context.Context,
 		startTime, endTime time.Time,
 		opts ...IteratorOption) iter.Seq2[ChannelEdge, error]
diff --git a/graph/db/kv_store.go b/graph/db/kv_store.go
index aa32f75..951c879 100644
--- a/graph/db/kv_store.go
+++ b/graph/db/kv_store.go
@@ -2286,8 +2286,9 @@ func (c *KVStore) fetchNextChanUpdateBatch(
 		// Now we'll read items up to the batch size, exiting early if
 		// we exceed the ending time.
 		for len(batch) < state.batchSize && indexKey != nil {
-			// If we're at the end, then we'll break out now.
-			if bytes.Compare(indexKey, endTimeBytes[:]) > 0 {
+			// If we've reached or passed the end time, break
+			// out. Per BOLT 07, the end time is exclusive.
+			if bytes.Compare(indexKey, endTimeBytes[:]) >= 0 {
 				break
 			}
 
@@ -2373,10 +2374,11 @@ func (c *KVStore) fetchNextChanUpdateBatch(
 			indexKey, _ = updateCursor.Next()
 		}
 
-		// If we haven't yet crossed the endTimeBytes, then we still
-		// have more entries to deliver.
+		// If we haven't yet reached the endTimeBytes, then we still
+		// have more entries to deliver. The end time is exclusive
+		// per BOLT 07.
 		if indexKey != nil &&
-			bytes.Compare(indexKey, endTimeBytes[:]) <= 0 {
+			bytes.Compare(indexKey, endTimeBytes[:]) < 0 {
 
 			hasMore = true
 		}
@@ -2394,7 +2396,8 @@ func (c *KVStore) fetchNextChanUpdateBatch(
 }
 
 // ChanUpdatesInHorizon returns all the known channel edges which have at least
-// one edge that has an update timestamp within the specified horizon.
+// one edge that has an update timestamp greater than or equal to startTime and
+// less than endTime, i.e. the range [startTime, endTime) per BOLT 07.
 func (c *KVStore) ChanUpdatesInHorizon(_ context.Context,
 	startTime, endTime time.Time,
 	opts ...IteratorOption) iter.Seq2[ChannelEdge, error] {
@@ -2568,9 +2571,10 @@ func (c *KVStore) fetchNextNodeBatch(
 			// Extract the timestamp from the index key (first 8
 			// bytes). Only compare timestamps, not the full key
 			// with pubkey.
+			// The end time is exclusive per BOLT 07.
 			keyTimestamp := byteOrder.Uint64(indexKey[:8])
 			endTimestamp := uint64(state.endTime.Unix())
-			if keyTimestamp > endTimestamp {
+			if keyTimestamp >= endTimestamp {
 				break
 			}
 
@@ -2607,12 +2611,13 @@ func (c *KVStore) fetchNextNodeBatch(
 			indexKey, _ = updateCursor.Next()
 		}
 
-		// If we haven't yet crossed the endTime, then we still
-		// have more entries to deliver.
+		// If we haven't yet reached the endTime, then we still
+		// have more entries to deliver. The end time is exclusive
+		// per BOLT 07.
 		if indexKey != nil {
 			keyTimestamp := byteOrder.Uint64(indexKey[:8])
 			endTimestamp := uint64(state.endTime.Unix())
-			if keyTimestamp <= endTimestamp {
+			if keyTimestamp < endTimestamp {
 				hasMore = true
 			}
 		}
@@ -2644,8 +2649,9 @@ func (c *KVStore) fetchNextNodeBatch(
 	return nodeBatch, hasMore, nil
 }
 
-// NodeUpdatesInHorizon returns all the known lightning node which have an
-// update timestamp within the passed range.
+// NodeUpdatesInHorizon returns all the known lightning nodes which have an
+// update timestamp greater than or equal to startTime and less than endTime,
+// i.e. the range [startTime, endTime) per BOLT 07.
 func (c *KVStore) NodeUpdatesInHorizon(_ context.Context, startTime,
 	endTime time.Time,
 	opts ...IteratorOption) iter.Seq2[*models.Node, error] {
diff --git a/graph/db/sql_store.go b/graph/db/sql_store.go
index ff1170a..a16fbf9 100644
--- a/graph/db/sql_store.go
+++ b/graph/db/sql_store.go
@@ -606,9 +606,10 @@ func (s *SQLStore) SetSourceNode(ctx context.Context,
 	}, sqldb.NoOpReset)
 }
 
-// NodeUpdatesInHorizon returns all the known lightning node which have an
-// update timestamp within the passed range. This method can be used by two
-// nodes to quickly determine if they have the same set of up to date node
+// NodeUpdatesInHorizon returns all the known lightning nodes which have an
+// update timestamp greater than or equal to startTime and less than endTime,
+// i.e. the range [startTime, endTime) per BOLT 07. This method can be used by
+// two nodes to quickly determine if they have the same set of up to date node
 // announcements.
 //
 // NOTE: This is part of the Store interface.
@@ -1161,7 +1162,8 @@ func (s *SQLStore) updateChanCacheBatch(v lnwire.GossipVersion,
 }
 
 // ChanUpdatesInHorizon returns all the known channel edges which have at least
-// one edge that has an update timestamp within the specified horizon.
+// one edge that has an update timestamp greater than or equal to startTime and
+// less than endTime, i.e. the range [startTime, endTime) per BOLT 07.
 //
 // Iterator Lifecycle:
 // 1. Initialize state (edgesSeen map, cache tracking, pagination cursors)
diff --git a/sqldb/sqlc/graph.sql.go b/sqldb/sqlc/graph.sql.go
index dc0a064..52d47ea 100644
--- a/sqldb/sqlc/graph.sql.go
+++ b/sqldb/sqlc/graph.sql.go
@@ -2122,7 +2122,7 @@ const getNodesByLastUpdateRange = `-- name: GetNodesByLastUpdateRange :many
 SELECT id, version, pub_key, alias, last_update, color, signature, block_height
 FROM graph_nodes
 WHERE last_update >= $1
-  AND last_update <= $2
+  AND last_update < $2
   -- Pagination: We use (last_update, pub_key) as a compound cursor.
   -- This ensures stable ordering and allows us to resume from where we left off.
   -- We use COALESCE with -1 as sentinel since timestamps are always positive.
diff --git a/sqldb/sqlc/queries/graph.sql b/sqldb/sqlc/queries/graph.sql
index 78c1ebe..e77c90c 100644
--- a/sqldb/sqlc/queries/graph.sql
+++ b/sqldb/sqlc/queries/graph.sql
@@ -228,7 +228,7 @@ ORDER BY node_id, type, position;
 SELECT *
 FROM graph_nodes
 WHERE last_update >= @start_time
-  AND last_update <= @end_time
+  AND last_update < @end_time
   -- Pagination: We use (last_update, pub_key) as a compound cursor.
   -- This ensures stable ordering and allows us to resume from where we left off.
   -- We use COALESCE with -1 as sentinel since timestamps are always positive.