diff --git a/.github/workflows/release.yml b/.github/workflows/release-c.yml
similarity index 100%
rename from .github/workflows/release.yml
rename to .github/workflows/release-c.yml
diff --git a/.github/workflows/wheels.yml b/.github/workflows/wheels.yml
index d15b8e378e..0448ea4359 100644
--- a/.github/workflows/wheels.yml
+++ b/.github/workflows/wheels.yml
@@ -8,6 +8,7 @@ on:
 
 jobs:
   build-wheels:
+    if: "!startsWith(github.ref, 'refs/tags/C_')"
     uses: tskit-dev/.github/.github/workflows/build-wheels.yml@v14
     with:
       pyproject-directory: python
diff --git a/python/CHANGELOG.rst b/python/CHANGELOG.rst
index 68c4224581..2d79eee608 100644
--- a/python/CHANGELOG.rst
+++ b/python/CHANGELOG.rst
@@ -1,3 +1,9 @@
+--------------------
+[1.0.3] - 2026-XX-XX
+--------------------
+
+In development
+
 --------------------
 [1.0.2] - 2026-03-06
 --------------------
diff --git a/python/tskit/_version.py b/python/tskit/_version.py
index bfdc01100f..2acaacae49 100644
--- a/python/tskit/_version.py
+++ b/python/tskit/_version.py
@@ -1,4 +1,4 @@
 # Definitive location for the version number.
 # During development, should be x.y.z.devN
 # For beta should be x.y.zbN
-tskit_version = "1.0.2"
+tskit_version = "1.0.3.dev1"