diff --git a/src/timetable_gui.cpp b/src/timetable_gui.cpp
index 4749477bf8..629620241b 100644
--- a/src/timetable_gui.cpp
+++ b/src/timetable_gui.cpp
@@ -86,20 +86,20 @@ static inline TimerGameTick::Ticks TicksPerTimetableUnit()
 }
 
 /**
- * Determine if a vehicle should be shown as late, depending on the timetable display setting.
- * @param v The vehicle in question.
+ * Determine if a vehicle should be shown as late or early, using a threshold depending on the timetable display setting.
+ * @param ticks The number of ticks that the vehicle is late or early.
  * @param round_to_day When using ticks, if we should round up to the nearest day.
- * @return True if the vehicle is later than the threshold.
+ * @return True if the vehicle is outside the "on time" threshold, either early or late.
  */
-bool VehicleIsAboveLatenessThreshold(const Vehicle *v, bool round_to_day)
+bool VehicleIsAboveLatenessThreshold(TimerGameTick::Ticks ticks, bool round_to_day)
 {
 	switch (_settings_client.gui.timetable_mode) {
 		case TimetableMode::Days:
-			return v->lateness_counter > Ticks::DAY_TICKS;
+			return ticks > Ticks::DAY_TICKS;
 		case TimetableMode::Seconds:
-			return v->lateness_counter > Ticks::TICKS_PER_SECOND;
+			return ticks > Ticks::TICKS_PER_SECOND;
 		case TimetableMode::Ticks:
-			return v->lateness_counter > (round_to_day ? Ticks::DAY_TICKS : 0);
+			return ticks > (round_to_day ? Ticks::DAY_TICKS : 0);
 		default:
 			NOT_REACHED();
 	}
@@ -501,7 +501,7 @@ struct TimetableWindow : Window {
 		int selected = this->sel_index;
 
 		Rect tr = r.Shrink(WidgetDimensions::scaled.framerect);
-		bool show_late = this->show_expected && VehicleIsAboveLatenessThreshold(v, true);
+		bool show_late = this->show_expected && VehicleIsAboveLatenessThreshold(v->lateness_counter, true);
 		TimerGameTick::Ticks offset = show_late ? 0 : -v->lateness_counter;
 
 		for (int i = this->vscroll->GetPosition(); i / 2 < v->GetNumOrders(); ++i) { // note: i is also incremented in the loop
@@ -586,7 +586,7 @@ struct TimetableWindow : Window {
 		} else if (!HasBit(v->vehicle_flags, VF_TIMETABLE_STARTED)) {
 			/* We aren't running on a timetable yet. */
 			DrawString(tr, STR_TIMETABLE_STATUS_NOT_STARTED);
-		} else if (!VehicleIsAboveLatenessThreshold(v, false)) {
+		} else if (!VehicleIsAboveLatenessThreshold(abs(v->lateness_counter), false)) {
 			/* We are on time. */
 			DrawString(tr, STR_TIMETABLE_STATUS_ON_TIME);
 		} else {