diff --git a/src/timetable_cmd.cpp b/src/timetable_cmd.cpp
--- a/src/timetable_cmd.cpp
+++ b/src/timetable_cmd.cpp
@@ -292,10 +292,10 @@ CommandCost CmdSetTimetableStart(TileInd
 		}
 
 		int total_duration = v->orders.list->GetTimetableTotalDuration();
-		int num_vehs = vehs.Length();
+		int num_vehs = vehs.size();
 
 		if (num_vehs >= 2) {
-			QSortT(vehs.Begin(), vehs.Length(), &VehicleTimetableSorter);
+			QSortT(vehs.Begin(), vehs.size(), &VehicleTimetableSorter);
 		}
 
 		int base = vehs.FindIndex(v);