Fix VTOL influence removal timing on take-off

OpenRA.Mods.Common/Activities/Air/TakeOff.cs

@@ -22,6 +22,7 @@ public class TakeOff : Activity
 		readonly IMove move;
 		readonly Target target;
 		bool moveToRallyPoint;
+		bool removedInfluence;
 
 		public TakeOff(Actor self, Target target)
 		{
@@ -48,14 +49,33 @@ protected override void OnFirstRun(Actor self)
 			if (aircraft.ForceLanding)
 				return;
 
-			// We are taking off, so remove reservation and influence in ground cells.
-			aircraft.UnReserve();
-			aircraft.RemoveInfluence();
+			// Only non-VTOLs should remove influence and reservation immediately.
+			// VTOLs will do this after reaching CruiseAltitude or when activity is cancelled.
+			if (!aircraft.Info.VTOL)
+			{
+				// We are taking off, so remove reservation and influence in ground cells.
+				aircraft.UnReserve();
+				aircraft.RemoveInfluence();
+				removedInfluence = true;
+			}
 
 			if (aircraft.Info.TakeoffSounds.Length > 0)
 				Game.Sound.Play(SoundType.World, aircraft.Info.TakeoffSounds, self.World, aircraft.CenterPosition);
 		}
 
+		protected override void OnLastRun(Actor self)
+		{
+			if (aircraft.ForceLanding)
+				return;
+
+			if (removedInfluence || !aircraft.Info.VTOL)
+				return;
+
+			// We are taking off, so remove reservation and influence in ground cells.
+			aircraft.UnReserve();
+			aircraft.RemoveInfluence();
+		}
+
 		public override Activity Tick(Actor self)
 		{
 			if (ChildActivity != null)
@@ -95,6 +115,14 @@ public override Activity Tick(Actor self)
 				}
 			}
 
+			if (!removedInfluence)
+			{
+				// We have taken off, so remove reservation and influence in ground cells if that hasn't happened yet.
+				aircraft.UnReserve();
+				aircraft.RemoveInfluence();
+				removedInfluence = true;
+			}
+
 			// Checking for NextActivity == null again in case another activity was queued while taking off
 			if (moveToRallyPoint && NextActivity == null)
 			{