diff --git a/TEM_comms/stage/aperture.py b/TEM_comms/stage/aperture.py
index 9066349..b6ccec3 100644
--- a/TEM_comms/stage/aperture.py
+++ b/TEM_comms/stage/aperture.py
@@ -7,6 +7,6 @@ class Command(BaseMessage):
 
 
 class Status(BaseMessage):
-    current_aperture: int
+    current_aperture: int | None
     calibrated: bool
     error: str = ""
diff --git a/pyproject.toml b/pyproject.toml
index b2eb9d3..a58b0e6 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,6 +1,6 @@
 [project]
 name = "pigeon-tem-comms"
-version = "0.4.3"
+version = "0.4.4"
 authors = [
   { name="Cameron Devine", email="cameron.devine@alleninstitute.org" },
 ]