diff --git a/src/newgrf_object.cpp b/src/newgrf_object.cpp
--- a/src/newgrf_object.cpp
+++ b/src/newgrf_object.cpp
@@ -54,15 +54,23 @@ ObjectSpec _object_specs[NUM_OBJECTS];
 }
 
 /**
+ * Check whether the object might be available at some point in this game with the current game mode.
+ * @return true if it might be available.
+ */
+bool ObjectSpec::IsEverAvailable() const
+{
+	return this->enabled && HasBit(this->climate, _settings_game.game_creation.landscape) &&
+			(this->flags & (_game_mode != GM_EDITOR ? OBJECT_FLAG_ONLY_IN_SCENEDIT : OBJECT_FLAG_ONLY_IN_GAME)) == 0;
+}
+
+/**
  * Check whether the object is available at this time.
  * @return true if it is available.
  */
 bool ObjectSpec::IsAvailable() const
 {
-	return this->enabled && _date > this->introduction_date &&
-			(_date < this->end_of_life_date || this->end_of_life_date < this->introduction_date + 365) &&
-			HasBit(this->climate, _settings_game.game_creation.landscape) &&
-			(flags & (_game_mode != GM_EDITOR ? OBJECT_FLAG_ONLY_IN_SCENEDIT : OBJECT_FLAG_ONLY_IN_GAME)) == 0;
+	return this->IsEverAvailable() && _date > this->introduction_date &&
+			(_date < this->end_of_life_date || this->end_of_life_date < this->introduction_date + 365);
 }
 
 /**
diff --git a/src/newgrf_object.h b/src/newgrf_object.h
--- a/src/newgrf_object.h
+++ b/src/newgrf_object.h
@@ -82,6 +82,7 @@ struct ObjectSpec {
 	 */
 	Money GetClearCost() const { return GetPrice(PR_CLEAR_OBJECT, this->clear_cost_multiplier, this->grf_prop.grffile, 0); }
 
+	bool IsEverAvailable() const;
 	bool IsAvailable() const;
 	uint Index() const;