diff --git a/test/external/external_benchmark_ast.py b/test/external/external_benchmark_ast.py
index fa7ce0c6..b7d6dc89 100644
--- a/test/external/external_benchmark_ast.py
+++ b/test/external/external_benchmark_ast.py
@@ -19,7 +19,7 @@ if __name__ == "__main__":
   no_rewrite: List[float] = []
   for k,v in output_groups.items():
     st = time.perf_counter_ns()
-    lsi = _lower_lazybuffer(v, realizes)
+    lsi = _lower_lazybuffer(v, realizes)[0]
     et = time.perf_counter_ns() - st
     if lsi.ast.op is UOps.EXT: continue
     no_rewrite.append(et*1e-6)
@@ -30,7 +30,7 @@ if __name__ == "__main__":
   with Context(AST_REWRITE=1):
     for k,v in output_groups.items():
       st = time.perf_counter_ns()
-      lsi = _lower_lazybuffer(v, realizes)
+      lsi = _lower_lazybuffer(v, realizes)[0]
       bufs.append(v)
       et = time.perf_counter_ns() - st
       if lsi.ast.op is UOps.EXT: continue
diff --git a/tinygrad/engine/schedule.py b/tinygrad/engine/schedule.py
index ac898e41..2ccfe41e 100644
--- a/tinygrad/engine/schedule.py
+++ b/tinygrad/engine/schedule.py
@@ -6,7 +6,7 @@ from tinygrad.ops import BUFFER_UOPS, REDUCE_ALU, MetaOps, ReduceOps, UNSAFE_PAD
 from tinygrad.rewrite import PatternMatcher, UPat, graph_rewrite
 from tinygrad.engine.graph import log_lazybuffer, realized_lazybuffer
 from tinygrad.helpers import GRAPH, DEBUG, MULTIOUTPUT, SAVE_SCHEDULE, FUSE_CONV_BW, FUSE_ARANGE, AST_REWRITE, \
-                             GlobalCounters, all_same, colored, prod, dedup, all_int, merge_dicts, getenv, Metadata, unwrap
+                             GlobalCounters, all_same, colored, flatten, prod, dedup, all_int, merge_dicts, getenv, Metadata, unwrap
 from tinygrad.shape.symbolic import Variable, sint
 from tinygrad.dtype import ConstType, ImageDType, PtrDType, dtypes
 from tinygrad.lazy import LazyBuffer
@@ -202,15 +202,15 @@ reduceop_fusor = PatternMatcher([
   (UPat({UOps.ALU, UOps.CAST, UOps.BITCAST, UOps.STORE}, name="root"), push_reduceop_shape),
 ])
 
-def _lower_lazybuffer(outs:List[LazyBuffer], realizes:Dict[LazyBuffer, None]) -> LBScheduleItem:
+def _lower_lazybuffer(outs:List[LazyBuffer], realizes:Dict[LazyBuffer, None]) -> List[LBScheduleItem]:
   """describe the computation for a LazyBuffer with UOp + inputs + var_vals"""
   if (out:=outs[0]).op is MetaOps.COPY and getenv("USE_COPY_KERNEL") and out.device.split(":")[0] == out.srcs[0].device.split(":")[0]:
     st_uop = ShapeTracker.from_shape(out.arg).to_uop()
     rd = UOp(UOps.LOAD, dtypes.uint8, (UOp(UOps.DEFINE_GLOBAL, PtrDType(dtypes.uint8), (), 1), st_uop))
     wr = UOp(UOps.STORE, None, (UOp(UOps.DEFINE_GLOBAL, PtrDType(out.dtype), (), 0), st_uop, rd))
-    return LBScheduleItem(UOp(UOps.SINK, None, (wr,)), outs, [x.base for x in out.srcs])
+    return [LBScheduleItem(UOp(UOps.SINK, None, (wr,)), outs, [x.base for x in out.srcs])]
   if out.op in {MetaOps.CUSTOM, MetaOps.COPY, MetaOps.EMPTY, MetaOps.VIEW}:
-    return LBScheduleItem(UOp(UOps.EXT, out.dtype, (), (out.op, out.arg)), outs, [x.base for x in out.srcs])
+    return [LBScheduleItem(UOp(UOps.EXT, out.dtype, (), (out.op, out.arg)), outs, [x.base for x in out.srcs])]
   reduce_info: Dict[Tuple[LazyBuffer, ShapeTracker], Tuple[ShapeTracker, Tuple[int, ...]]] = {}
   if not AST_REWRITE:
     # push through all movementops between reduceops
@@ -245,7 +245,7 @@ def _lower_lazybuffer(outs:List[LazyBuffer], realizes:Dict[LazyBuffer, None]) ->
   sink = UOp(UOps.SINK, None, tuple(ast))
   if AST_REWRITE:
     sink = graph_rewrite(sink, reduceop_fusor)
-  return LBScheduleItem(sink, outs, list(inputs), var_vals, dedup([x[0].metadata for x in cache if x[0].metadata and x[0] not in inputs]))
+  return [LBScheduleItem(sink, outs, list(inputs), var_vals, dedup([x[0].metadata for x in cache if x[0].metadata and x[0] not in inputs]))]
 
 # *** DAG creation: decide which LazyBuffers should realize ***
 
@@ -424,7 +424,7 @@ def _graph_schedule(outs:List[LazyBuffer], seen:Set[LazyBuffer]) -> \
   """create a graph for realizing the outputs"""
   output_groups, realizes, assign_targets = _get_output_groups(outs, seen)
   # preschedule all buffers in realizes
-  prescheduled = [_lower_lazybuffer(group, realizes) for group in output_groups.values()]
+  prescheduled = flatten([_lower_lazybuffer(group, realizes) for group in output_groups.values()])
   schedule_targets = {out:lsi for lsi in prescheduled for out in lsi.outputs}
 
   graph: DefaultDict[LBScheduleItem, List[LBScheduleItem]] = defaultdict(list)