diff --git a/test_libs/pyspec/eth2spec/test/block_processing/test_process_block_header.py b/test_libs/pyspec/eth2spec/test/block_processing/test_process_block_header.py
index 3faf51e1b..9918e6283 100644
--- a/test_libs/pyspec/eth2spec/test/block_processing/test_process_block_header.py
+++ b/test_libs/pyspec/eth2spec/test/block_processing/test_process_block_header.py
@@ -49,8 +49,9 @@ def test_success_block_header(state):
 
 @spec_state_test
 def test_invalid_slot_block_header(state):
-    block = build_empty_block_for_next_slot(state, signed=True)
+    block = build_empty_block_for_next_slot(state, signed=False)
     block.slot = state.slot + 2  # invalid slot
+    sign_block(state, block)
 
     yield from run_block_header_processing(state, block, valid=False)
 
diff --git a/test_libs/pyspec/eth2spec/test/context.py b/test_libs/pyspec/eth2spec/test/context.py
index a9eaea349..4c8ff255b 100644
--- a/test_libs/pyspec/eth2spec/test/context.py
+++ b/test_libs/pyspec/eth2spec/test/context.py
@@ -57,7 +57,7 @@ def bls_switch(fn):
     """
     def entry(*args, **kw):
         old_state = bls.bls_active
-        bls.bls_active = kw.pop('bls_active', False)
+        bls.bls_active = kw.pop('bls_active', True)
         fn(*args, **kw)
         bls.bls_active = old_state
     return entry