diff --git a/.github/workflows/nightly-mac-ci.yml b/.github/workflows/nightly-mac-ci.yml
index be38c703..ddc9d189 100644
--- a/.github/workflows/nightly-mac-ci.yml
+++ b/.github/workflows/nightly-mac-ci.yml
@@ -26,16 +26,6 @@ jobs:
       run-tests: true
       use-ccache: false
 
-  nightly-mac-ci-2_1_x:
-    uses: eProsima/Fast-CDR/.github/workflows/reusable-ci.yml@2.1.x
-    with:
-      os-version: 'macos-13'
-      label: 'nightly-mac-ci-2.1.x'
-      fastcdr-branch: '2.1.x'
-      run-build: true
-      run-tests: true
-      use-ccache: false
-
   nightly-mac-ci-1_1_x:
     uses: eProsima/Fast-CDR/.github/workflows/reusable-ci.yml@1.1.x
     with:
@@ -49,7 +39,7 @@ jobs:
   nightly-mac-ci-1_0_x:
     uses: eProsima/Fast-CDR/.github/workflows/reusable-ci.yml@1.0.x
     with:
-      os-version: 'mac-13'
+      os-version: 'macos-13'
       label: 'nightly-mac-ci-1.0.x'
       fastcdr-branch: '1.0.x'
       run-build: true
diff --git a/.github/workflows/nightly-ubuntu-ci.yml b/.github/workflows/nightly-ubuntu-ci.yml
index 6d986c05..48cfdfa8 100644
--- a/.github/workflows/nightly-ubuntu-ci.yml
+++ b/.github/workflows/nightly-ubuntu-ci.yml
@@ -26,16 +26,6 @@ jobs:
       run-tests: true
       use-ccache: false
 
-  nightly-ubuntu-ci-2_1_x:
-    uses: eProsima/Fast-CDR/.github/workflows/reusable-ci.yml@2.1.x
-    with:
-      os-version: 'ubuntu-22.04'
-      label: 'nightly-ubuntu-ci-2.1.x'
-      fastcdr-branch: '2.1.x'
-      run-build: true
-      run-tests: true
-      use-ccache: false
-
   nightly-ubuntu-ci-1_1_x:
     uses: eProsima/Fast-CDR/.github/workflows/reusable-ci.yml@1.1.x
     with:
diff --git a/.github/workflows/nightly-windows-ci.yml b/.github/workflows/nightly-windows-ci.yml
index 57d2a226..cc292101 100644
--- a/.github/workflows/nightly-windows-ci.yml
+++ b/.github/workflows/nightly-windows-ci.yml
@@ -40,23 +40,6 @@ jobs:
       run-tests: true
       use-ccache: false
 
-  nightly-windows-ci-2_1_x:
-    strategy:
-      fail-fast: false
-      matrix:
-        vs-toolset:
-          - 'v141'
-          - 'v142'
-    uses: eProsima/Fast-CDR/.github/workflows/reusable-ci.yml@2.1.x
-    with:
-      os-version: 'windows-2019'
-      vs-toolset: ${{ matrix.vs-toolset }}
-      label: 'nightly-windows-${{ matrix.vs-toolset }}-ci-2.1.x'
-      fastcdr-branch: '2.1.x'
-      run-build: true
-      run-tests: true
-      use-ccache: false
-
   nightly-windows-ci-1_1_x:
     strategy:
       fail-fast: false