So my world procedurally places the instances where they should go. I have many of the properties exposed through UProperty so that I can tweak the result in view the update in the editor. When BeginPlay occurs the world takes about 4 seconds to spawn in. So while play is going on I will tweak the numbers. The very first time I tweak a UProperty while play is going on it takes about 45 seconds for the world to refresh/ unfreeze and control is back. Any further tweaks to UProperties result in about 5-6 second update. This seems odd to me. When the UProperty is modified PostEditChangeProperty is called and in there I update the values to my terrain generator, and then ClearInstance(). Then I update their data and respawn the instances. The 45 second first time delay is mostly what I’m wondering about. The time for the update from playing, or any tweak after the first UProperty update is just from the number of instances being updated. But I don’t understand why the first time causes a 45 second delay. Any ideas?