diff --git a/.github/workflows/branches.yml b/.github/workflows/branches.yml
new file mode 100644
index 0000000..1232a16
--- /dev/null
+++ b/.github/workflows/branches.yml
@@ -0,0 +1,42 @@
+name: Update belowS20 and aboveS20 Branches
+
+on:
+  push:
+    branches:
+      - master
+
+permissions:
+  contents: write
+
+jobs:
+  update-branches:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout master branch
+        uses: actions/checkout@v3
+
+      - name: Set up Git user
+        run: |
+          git config user.name "GitHub Actions"
+          git config user.email "actions@github.com"
+
+      - name: Delete branches locally and on remote
+        run: |
+          git push origin --delete belowS20 || true
+          git push origin --delete aboveS20 || true
+          git branch -D belowS20 || true
+          git branch -D aboveS20 || true
+
+      - name: Create belowS20 branch from master
+        run: |
+          git checkout -b belowS20
+          git push origin belowS20
+
+      - name: Create aboveS20 branch from master and modify inc.h
+        run: |
+          git checkout master
+          git checkout -b aboveS20
+          echo '#define ABOVE_S20' | cat - "./Project Reboot 3.0/inc.h" > temp && mv temp "./Project Reboot 3.0/inc.h"
+          git add "./Project Reboot 3.0/inc.h"
+          git commit -m "Add #define ABOVE_S20 to inc.h in aboveS20 branch"
+          git push origin aboveS20
diff --git a/.github/workflows/msbuild.yml b/.github/workflows/msbuild.yml
index 6a34da3..c9411eb 100644
--- a/.github/workflows/msbuild.yml
+++ b/.github/workflows/msbuild.yml
@@ -2,9 +2,9 @@ name: MSBuild
 
 on:
   push:
-    branches: [ "master" ]
+    branches: [ "aboveS20", "belowS20" ]
   pull_request:
-    branches: [ "master" ]
+    branches: [ "aboveS20", "belowS20" ]
 
 env:
   # Path to the solution file relative to the root of the project.