Quick answer: Unreal PCG async-spawning actors mid-streaming when level unloads? Spawned actors orphan in the unloading level - listen for level-unload and cancel pending PCG generations.
Level streams out while PCG is generating; actors spawn into a dead level; warnings.
Cancel on unload
Hook LevelUnload event; cancel PCG generations targeting that level.
Or only generate when level is loaded
Check LevelLoaded before triggering PCG. Sync-load triggered generation.
Test level streaming cycle
Stream in, generate, stream out; verify no warnings. The cycle reproduces the bug.
“Async work outlives its context. Cancellation is the bridge.”
If your PCG runs in streamed levels, the cancellation is mandatory. The warnings are noise; the orphans are real.