When lowering dynamic event controls, destructive pre-clear updates were inserted with addHereThisAsNext() on the original node and then that node was replaced. This could leave leaked/orphaned nodes under leak-checking runs.
Build an explicit replacement stmt chain instead:
[pre-clear stmts] -> trigger loop -> awaitResumption,
and replace the original control with the chain head. Keep the loop-only path unchanged when no destructive pre-clear is needed.
Nick Brereton