diff --git a/.github/workflows/ci-build.yaml b/.github/workflows/ci-build.yaml
index 945163e2..feddc427 100644
--- a/.github/workflows/ci-build.yaml
+++ b/.github/workflows/ci-build.yaml
@@ -3,6 +3,7 @@ on:
   push:
     branches:
       - 'master'
+
   pull_request:
     branches:
       - 'master'
@@ -155,8 +156,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        k3s-version: [v1.19.2, v1.16.15]
-        # k3s-version: [v1.19.2, v1.18.9, v1.17.11, v1.16.15]
+        k3s-version: [v1.20.2, v1.16.15]        
     env:
       GITHUB_TOKEN: ${{ secrets.GH_TOKEN }}
       GITLAB_TOKEN: ${{ secrets.GITLAB_TOKEN }}
@@ -174,6 +174,7 @@ jobs:
         uses: actions/checkout@v2
         with:
           repository: argoproj/argo-cd
+          path: argo-cd
           # Pin a specific commit to prevent Argo CD regressions from impacting us:
           # This version is verified to match a version consistent with the kustomize install yaml,
           # by 'hack/verify-argo-cd-versions.sh'.
@@ -184,84 +185,32 @@ jobs:
         uses: actions/setup-go@v2
         with:
           go-version: '1.16.4'
-      # Add same workaround for port 8084 as argoproj/argo-cd #5658
-      - name: GH actions workaround - Kill XSP4 process
-        run: |
-          sudo pkill mono || true
-      - name: Install K3S
-        env:
-          INSTALL_K3S_VERSION: ${{ matrix.k3s-version }}+k3s1
-        run: |
-          set -x
-          curl -sfL https://get.k3s.io | sh -
-          sudo chmod -R a+rw /etc/rancher/k3s
-          sudo mkdir -p $HOME/.kube && sudo chown -R runner $HOME/.kube
-          sudo k3s kubectl config view --raw > $HOME/.kube/config
-          sudo chown runner $HOME/.kube/config
-          kubectl version
+
       - name: Restore go build cache
         uses: actions/cache@v1
         with:
           path: ~/.cache/go-build
           key: ${{ runner.os }}-go-build-v1-${{ github.run_id }}
-      - name: Add ~/go/bin to PATH
-        run: |
-          echo "/home/runner/go/bin" >> $GITHUB_PATH
-      - name: Add /usr/local/bin to PATH
-        run: |
-          echo "/usr/local/bin" >> $GITHUB_PATH
-      - name: Download Go dependencies
-        run: |
-          go mod download
-          go get github.com/mattn/goreman
-      - name: Install all tools required for building & testing
-        run: |
-          make install-test-tools-local
-      - name: Setup git username and email
-        run: |
-          git config --global user.name "John Doe"
-          git config --global user.email "john.doe@example.com"
-      - name: Pull Docker image required for tests
-        run: |
-          docker pull quay.io/dexidp/dex:v2.25.0
-          docker pull argoproj/argo-cd-ci-builder:v1.0.0
-          docker pull redis:5.0.10-alpine
-      - name: Create target directory for binaries in the build-process
-        run: |
-          mkdir -p dist
-          chown runner dist
-      - name: Run Argo CD E2E server and wait for it being available
-        timeout-minutes: 30
-        run: |
-          set -x
-          # Something is weird in GH runners -- there's a phantom listener for
-          # port 8080 which is not visible in netstat -tulpen, but still there
-          # with a HTTP listener. We have API server listening on port 8088
-          # instead.
-          make start-e2e-local 2>&1 | sed -r "s/[[:cntrl:]]\[[0-9]{1,3}m//g" > /tmp/e2e-server.log &
-          count=1
-          until curl -f http://127.0.0.1:8088/healthz; do
-            sleep 10;
-            if test $count -ge 180; then
-              echo "Timeout"
-              exit 1
-            fi
-            count=$((count+1))
-          done
+
       - name: Checkout latest applicationset code
         uses: actions/checkout@v2
         with:
-          path: applicationsets
-      - name: Run E2E test suite
+          path: applicationset
+
+      - name: Run E2E test setup
+        timeout-minutes: 20
+        env:
+          INSTALL_K3S_VERSION: ${{ matrix.k3s-version }}+k3s1
         run: |
-          set -x
-          cd "$GITHUB_WORKSPACE/applicationsets"
-          kubectl apply -f manifests/crds/argoproj.io_applicationsets.yaml
-          make build
-          make start-e2e 2>&1 | tee /tmp/appset-e2e-server.log &
-          # Uncomment this to see the Argo CD output alongside test output:
-          # tail -f /tmp/e2e-server.log &
-          make test-e2e
+          cd "$GITHUB_WORKSPACE/applicationset"
+          "hack/ci-e2e-setup.sh"
+
+      - name: Run E2E tests
+        timeout-minutes: 20
+        run: |
+          cd "$GITHUB_WORKSPACE/applicationset"
+          "hack/ci-e2e-run.sh"
+
       - name: Upload e2e-server logs
         uses: actions/upload-artifact@v2
         with:
diff --git a/.github/workflows/cron-master-on-stable.yaml b/.github/workflows/cron-master-on-stable.yaml
new file mode 100644
index 00000000..2f4a7764
--- /dev/null
+++ b/.github/workflows/cron-master-on-stable.yaml
@@ -0,0 +1,107 @@
+name: Nightly test of ApplicationSet 'master' on latest stable ArgoCD releases
+# This is useful for detecting regressions of ApplicationSet master branch against released Argo CD releases.
+
+on:
+  schedule:
+    - cron: '5 2 * * *'
+
+jobs:
+
+  test-e2e:
+    name: "Run E2E tests - K8s/Argo CD:"
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        k3s-version: [v1.20.2]
+        argo-release: [Latest, v2.1, v2.2]
+    env:
+      GOPATH: /home/runner/go
+      ARGOCD_FAKE_IN_CLUSTER: 'true'
+      ARGOCD_SSH_DATA_PATH: '/tmp/argo-e2e/app/config/ssh'
+      ARGOCD_TLS_DATA_PATH: '/tmp/argo-e2e/app/config/tls'
+      ARGOCD_E2E_SSH_KNOWN_HOSTS: '../fixture/certs/ssh_known_hosts'
+      ARGOCD_E2E_K3S: 'true'
+      ARGOCD_IN_CI: 'true'
+      ARGOCD_E2E_APISERVER_PORT: '8088'
+      ARGOCD_SERVER: '127.0.0.1:8088'
+      INSTALL_K3S_VERSION: ${{ matrix.k3s-version }}+k3s1
+      RELEASE_LIST_SEARCH_STRING: ${{ matrix.argo-release }}
+      GITHUB_TOKEN: ${{ secrets.GH_TOKEN }}
+      GITLAB_TOKEN: ${{ secrets.GITLAB_TOKEN }}
+
+#
+    steps:
+
+      - name: Login to GitHub
+        run: |
+          echo ${{ secrets.GITHUB_TOKEN }} | gh auth login --with-token
+
+      - name: Call GitHub CLI to find latest stable Argo CD release
+        id: get-argocd-stable
+        run: |
+          LATEST_RELEASE=`gh release list --repo argoproj/argo-cd | grep "$RELEASE_LIST_SEARCH_STRING" | head -n 1 | cut -f 1`
+          echo Latest release for $RELEASE_LIST_SEARCH_STRING is $LATEST_RELEASE
+          echo "::set-output name=latestRelease::$LATEST_RELEASE"
+
+      - name: Call GitHub CLI to find latest stable ApplicationSet release
+        id: get-appset-stable
+        run: |
+          LATEST_RELEASE=`gh release list --repo argoproj-labs/applicationset | grep "Latest" | cut -f 1`
+          echo Latest release for ApplicationSet is $LATEST_RELEASE
+          echo "::set-output name=latestRelease::$LATEST_RELEASE"
+
+
+      - name: Checkout latest Argo CD code
+        uses: actions/checkout@v2
+        with:
+          repository: argoproj/argo-cd
+          ref: ${{steps.get-argocd-stable.outputs.latestRelease}}
+          path: argo-cd
+          
+      - name: Setup Golang
+        uses: actions/setup-go@v2
+        with:
+          go-version: '1.16.4'
+
+      - name: Restore go build cache
+        uses: actions/cache@v1
+        with:
+          path: ~/.cache/go-build
+          key: ${{ runner.os }}-go-build-v1-${{ github.run_id }}
+
+      - name: Checkout latest applicationset code from latest stable release
+        uses: actions/checkout@v2
+        with:
+          path: applicationset
+          ref: ${{steps.get-appset-stable.outputs.latestRelease}}
+
+      - name: Checkout latest applicationset code from master
+        uses: actions/checkout@v2
+        with:
+          path: applicationset
+
+      - name: Run E2E test setup
+        timeout-minutes: 20
+        run: |
+          cd "$GITHUB_WORKSPACE/applicationset"
+          "hack/ci-e2e-setup.sh"
+
+      - name: Run E2E tests
+        timeout-minutes: 20
+        run: |
+          echo Running tests against Argo CD ${{steps.get-argocd-stable.outputs.latestRelease}} and ApplicationSet ${{steps.get-appset-stable.outputs.latestRelease}}
+          cd "$GITHUB_WORKSPACE/applicationset"
+          "hack/ci-e2e-run.sh"
+
+      - name: Upload e2e-server logs
+        uses: actions/upload-artifact@v2
+        with:
+          name: appset-e2e-server-k8s${{ matrix.k3s-version }}.log
+          path: /tmp/appset-e2e-server.log
+        if: ${{ failure() }}
+      - name: Upload other Argo CD server log
+        uses: actions/upload-artifact@v2
+        with:
+          name: argocd-e2e-server-k8s${{ matrix.k3s-version }}.log
+          path: /tmp/e2e-server.log
+        if: ${{ failure() }}
diff --git a/.github/workflows/cron-master.yaml b/.github/workflows/cron-master.yaml
new file mode 100644
index 00000000..db861217
--- /dev/null
+++ b/.github/workflows/cron-master.yaml
@@ -0,0 +1,83 @@
+name: Nightly test of ApplicationSet 'master' branch against latest Argo CD 'master' branch
+# This is useful for catching recent regressions between master branches of Argo CD and ApplicationSet.
+
+on:
+  schedule:
+    - cron: '5 2 * * *'
+
+  push:
+    branches:
+      - 'cron-test-argocd'
+
+
+jobs:
+
+  test-e2e:
+    name: Run end-to-end tests
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        k3s-version: [v1.20.2]
+    env:
+      GOPATH: /home/runner/go
+      ARGOCD_FAKE_IN_CLUSTER: 'true'
+      ARGOCD_SSH_DATA_PATH: '/tmp/argo-e2e/app/config/ssh'
+      ARGOCD_TLS_DATA_PATH: '/tmp/argo-e2e/app/config/tls'
+      ARGOCD_E2E_SSH_KNOWN_HOSTS: '../fixture/certs/ssh_known_hosts'
+      ARGOCD_E2E_K3S: 'true'
+      ARGOCD_IN_CI: 'true'
+      ARGOCD_E2E_APISERVER_PORT: '8088'
+      ARGOCD_SERVER: '127.0.0.1:8088'
+      INSTALL_K3S_VERSION: ${{ matrix.k3s-version }}+k3s1
+      GITHUB_TOKEN: ${{ secrets.GH_TOKEN }}
+      GITLAB_TOKEN: ${{ secrets.GITLAB_TOKEN }}
+
+    steps:
+          
+      - name: Checkout latest Argo CD code
+        uses: actions/checkout@v2
+        with:
+          repository: argoproj/argo-cd
+          ref: master
+          path: argo-cd
+          
+      - name: Setup Golang
+        uses: actions/setup-go@v2
+        with:
+          go-version: '1.16.4'
+
+      - name: Restore go build cache
+        uses: actions/cache@v1
+        with:
+          path: ~/.cache/go-build
+          key: ${{ runner.os }}-go-build-v1-${{ github.run_id }}
+
+      - name: Checkout latest applicationset code
+        uses: actions/checkout@v2
+        with:
+          path: applicationset
+
+      - name: Run E2E test setup
+        timeout-minutes: 20
+        run: |
+          cd "$GITHUB_WORKSPACE/applicationset"
+          "hack/ci-e2e-setup.sh"
+
+      - name: Run E2E tests
+        timeout-minutes: 20
+        run: |
+          cd "$GITHUB_WORKSPACE/applicationset"
+          "hack/ci-e2e-run.sh"
+
+      - name: Upload e2e-server logs
+        uses: actions/upload-artifact@v2
+        with:
+          name: appset-e2e-server-k8s${{ matrix.k3s-version }}.log
+          path: /tmp/appset-e2e-server.log
+        if: ${{ failure() }}
+      - name: Upload other Argo CD server log
+        uses: actions/upload-artifact@v2
+        with:
+          name: argocd-e2e-server-k8s${{ matrix.k3s-version }}.log
+          path: /tmp/e2e-server.log
+        if: ${{ failure() }}
diff --git a/.github/workflows/cron-stable-on-stable.yaml b/.github/workflows/cron-stable-on-stable.yaml
new file mode 100644
index 00000000..247fcd50
--- /dev/null
+++ b/.github/workflows/cron-stable-on-stable.yaml
@@ -0,0 +1,129 @@
+name: Nightly test of latest stable releases of ApplicationSet against latest stable releases of ArgoCD
+# This is useful for catching regressions of released ApplicationSet versions, against release Argo CD versions.
+
+on:
+  schedule:
+    - cron: '5 2 * * *'
+
+  push:
+    branches:
+      - 'cron-test-argocd'
+
+jobs:
+
+  test-e2e:
+    name: "Run E2E tests - K8s/Argo CD:"
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        k3s-version: [v1.20.2]
+        argo-release: [Latest, v2.1, v2.2]
+    env:
+      GOPATH: /home/runner/go
+      ARGOCD_FAKE_IN_CLUSTER: 'true'
+      ARGOCD_SSH_DATA_PATH: '/tmp/argo-e2e/app/config/ssh'
+      ARGOCD_TLS_DATA_PATH: '/tmp/argo-e2e/app/config/tls'
+      ARGOCD_E2E_SSH_KNOWN_HOSTS: '../fixture/certs/ssh_known_hosts'
+      ARGOCD_E2E_K3S: 'true'
+      ARGOCD_IN_CI: 'true'
+      ARGOCD_E2E_APISERVER_PORT: '8088'
+      ARGOCD_SERVER: '127.0.0.1:8088'
+      INSTALL_K3S_VERSION: ${{ matrix.k3s-version }}+k3s1
+      RELEASE_LIST_SEARCH_STRING: ${{ matrix.argo-release }}
+      GITHUB_TOKEN: ${{ secrets.GH_TOKEN }}
+      GITLAB_TOKEN: ${{ secrets.GITLAB_TOKEN }}
+
+    steps:
+
+      - name: Login to GitHub
+        run: |
+          echo ${{ secrets.GITHUB_TOKEN }} | gh auth login --with-token
+
+      - name: Call GitHub CLI to find latest stable Argo CD release
+        id: get-argocd-stable
+        run: |
+          LATEST_RELEASE=`gh release list --repo argoproj/argo-cd | grep "$RELEASE_LIST_SEARCH_STRING" | head -n 1 | cut -f 1`
+          echo Latest release for $RELEASE_LIST_SEARCH_STRING is $LATEST_RELEASE
+          echo "::set-output name=latestRelease::$LATEST_RELEASE"
+
+      - name: Call GitHub CLI to find latest stable ApplicationSet release
+        id: get-appset-stable
+        run: |
+          LATEST_RELEASE=`gh release list --repo argoproj-labs/applicationset | grep "Latest" | cut -f 1`
+          echo Latest release for ApplicationSet is $LATEST_RELEASE
+          echo "::set-output name=latestRelease::$LATEST_RELEASE"
+
+
+      - name: Checkout latest Argo CD code
+        uses: actions/checkout@v2
+        with:
+          repository: argoproj/argo-cd
+          ref: ${{steps.get-argocd-stable.outputs.latestRelease}}
+          path: argo-cd
+          
+      - name: Setup Golang
+        uses: actions/setup-go@v2
+        with:
+          go-version: '1.16.4'
+
+      - name: Restore go build cache
+        uses: actions/cache@v1
+        with:
+          path: ~/.cache/go-build
+          key: ${{ runner.os }}-go-build-v1-${{ github.run_id }}
+
+      - name: Checkout latest applicationset code from latest stable release
+        uses: actions/checkout@v2
+        with:
+          path: applicationset
+          ref: ${{steps.get-appset-stable.outputs.latestRelease}}
+
+      - name: Checkout latest applicationset code from master
+        uses: actions/checkout@v2
+        with:
+          path: applicationset
+
+
+      - name: Checkout latest applicationset code from latest stable release
+        uses: actions/checkout@v2
+        with:
+          path: applicationset
+          ref: ${{steps.get-appset-stable.outputs.latestRelease}}
+
+      - name: Checkout latest applicationset code from master
+        uses: actions/checkout@v2
+        with:
+          path: applicationset-master
+
+      - name: Add test runner scripts from AppSet master to release branch
+        run: |
+          mkdir -p "$GITHUB_WORKSPACE/applicationset/hack"
+          cp "$GITHUB_WORKSPACE"/applicationset-master/hack/ci-e2e-*.sh "$GITHUB_WORKSPACE/applicationset/hack"
+          ls -l "$GITHUB_WORKSPACE/applicationset/hack"
+
+
+      - name: Run E2E test setup
+        timeout-minutes: 20
+        run: |
+          cd "$GITHUB_WORKSPACE/applicationset"
+          "hack/ci-e2e-setup.sh"
+
+      - name: Run E2E tests
+        timeout-minutes: 20
+        run: |
+          echo Running tests against Argo CD ${{steps.get-argocd-stable.outputs.latestRelease}} and ApplicationSet ${{steps.get-appset-stable.outputs.latestRelease}}
+          cd "$GITHUB_WORKSPACE/applicationset"
+          "hack/ci-e2e-run.sh"
+
+      - name: Upload e2e-server logs
+        uses: actions/upload-artifact@v2
+        with:
+          name: appset-e2e-server-k8s${{ matrix.k3s-version }}.log
+          path: /tmp/appset-e2e-server.log
+        if: ${{ failure() }}
+      - name: Upload other Argo CD server log
+        uses: actions/upload-artifact@v2
+        with:
+          name: argocd-e2e-server-k8s${{ matrix.k3s-version }}.log
+          path: /tmp/e2e-server.log
+        if: ${{ failure() }}
diff --git a/docs/Release-Checklist-Template.md b/docs/Release-Checklist-Template.md
index d084acdc..a877078c 100644
--- a/docs/Release-Checklist-Template.md
+++ b/docs/Release-Checklist-Template.md
@@ -58,6 +58,7 @@ Once complete, this is a set of checks to perform once you have a commit, tags,
 - Ensure that a PR is opened on the **master** branch that:
     - [ ] Increments the VERSION file (eg 0.1.0 to 0.2.0)
     - [ ] Verify VERSION file does not contain the letter `v` as a prefix to the versio number
+    - [ ] Update the CI jobs in `.github/workflows` to point to the latest Argo CD version (Run `grep -r -i "argo-release"` to find the version list.)
 
 ## Doc checklist
 - [ ] Ensure that https://readthedocs.org/projects/argocd-applicationset/versions/ points to the correct commit (commit that is at the HEAD of the release branch), for the `stable` and `v(version)` versions.
diff --git a/hack/ci-e2e-run.sh b/hack/ci-e2e-run.sh
new file mode 100755
index 00000000..9729b4aa
--- /dev/null
+++ b/hack/ci-e2e-run.sh
@@ -0,0 +1,24 @@
+#!/bin/bash
+
+if [ "$ARGOCD_IN_CI" != "true" ] ; then
+    echo "This script should only be run from GitHub actions."
+    exit 1
+fi
+
+set -e
+
+# Add ~/go/bin to PATH --------------------------------------------------------
+# Add /usr/local/bin to PATH
+
+export PATH=/home/runner/go/bin:/usr/local/bin:$PATH
+
+
+# Run E2E test suite ----------------------------------------------------------
+set -x
+cd "$GITHUB_WORKSPACE/applicationset"
+kubectl apply -f manifests/crds/argoproj.io_applicationsets.yaml
+make build
+make start-e2e 2>&1 | tee /tmp/appset-e2e-server.log &
+# Uncomment this to see the Argo CD output alongside test output:
+# tail -f /tmp/e2e-server.log &
+make test-e2e
diff --git a/hack/ci-e2e-setup.sh b/hack/ci-e2e-setup.sh
new file mode 100755
index 00000000..1e139289
--- /dev/null
+++ b/hack/ci-e2e-setup.sh
@@ -0,0 +1,76 @@
+#!/bin/bash
+
+if [ "$ARGOCD_IN_CI" != "true" ] ; then
+    echo "This script should only be run from GitHub actions."
+    exit 1
+fi
+
+set -e
+
+# GH actions workaround - Kill XSP4 process -----------------------------------
+
+
+# Add same workaround for port 8084 as argoproj/argo-cd #5658
+sudo pkill mono || true
+
+# Install K3S -----------------------------------------------------------------
+echo "Installing k3s"
+set -x
+curl -sfL https://get.k3s.io | sh -
+sudo chmod -R a+rw /etc/rancher/k3s
+sudo mkdir -p $HOME/.kube && sudo chown -R runner $HOME/.kube
+sudo k3s kubectl config view --raw > $HOME/.kube/config
+sudo chown runner $HOME/.kube/config
+kubectl version
+set +x
+
+# Add ~/go/bin to PATH --------------------------------------------------------
+# Add /usr/local/bin to PATH
+
+export PATH=/home/runner/go/bin:/usr/local/bin:$PATH
+
+# Download Go dependencies ----------------------------------------------------
+go mod download
+go get github.com/mattn/goreman
+
+# Install all tools required for building & testing ---------------------------
+
+cd "$GITHUB_WORKSPACE/argo-cd"
+
+echo "Install all tools required for building & testing"
+make install-test-tools-local
+
+
+# Setup git username and email ------------------------------------------------
+git config --global user.name "John Doe"
+git config --global user.email "john.doe@example.com"
+
+# Pull Docker image required for tests ----------------------------------------
+docker pull quay.io/dexidp/dex:v2.25.0
+docker pull argoproj/argo-cd-ci-builder:v1.0.0
+docker pull redis:6.2.4-alpine
+      
+# Create target directory for binaries in the build-process -------------------
+mkdir -p dist
+chown runner dist
+
+
+# Run Argo CD E2E server and wait for it being available ----------------------
+
+echo "Run Argo CD E2E server and wait for it being available"
+
+set -x
+# Something is weird in GH runners -- there's a phantom listener for
+# port 8080 which is not visible in netstat -tulpen, but still there
+# with a HTTP listener. We have API server listening on port 8088
+# instead.
+make start-e2e-local 2>&1 | sed -r "s/[[:cntrl:]]\[[0-9]{1,3}m//g" > /tmp/e2e-server.log &
+count=1
+until curl -f http://127.0.0.1:8088/healthz; do
+    sleep 10;
+    if test $count -ge 180; then
+        echo "Timeout"
+        exit 1
+    fi
+    count=$((count+1))
+done