Let's try a fresh start on this

.github/workflows/R-CMD-check.yaml

+# Workflow derived from https://github.com/r-lib/actions/tree/master/examples
+# Need help debugging build failures? Start at https://github.com/r-lib/actions#where-to-find-help
 on:
   push:
-    branches:
-      - main
+    branches: main
   pull_request:
-    branches:
-      - main
+    branches: main
 
 name: R-CMD-check
 
@@ -20,69 +20,30 @@ jobs:
         config:
           - {os: macOS-latest,   r: 'release'}
           - {os: windows-latest, r: 'release'}
-          - {os: ubuntu-18.04,   r: 'release'}
-          - {os: ubuntu-18.04,   r: 'oldrel-1'}
+          - {os: ubuntu-latest,   r: 'devel', http-user-agent: 'release'}
+          - {os: ubuntu-latest,   r: 'release'}
+          - {os: ubuntu-latest,   r: 'oldrel-1'}
 
     env:
-      R_REMOTES_NO_ERRORS_FROM_WARNINGS: true
-      RSPM: ${{ matrix.config.rspm }}
       GITHUB_PAT: ${{ secrets.GITHUB_TOKEN }}
+      R_KEEP_PKG_SOURCE: yes
 
     steps:
       - uses: actions/checkout@v2
 
-      - uses: r-lib/actions/setup-r@master
+      - uses: r-lib/actions/setup-pandoc@v1
+
+      - uses: r-lib/actions/setup-r@v1
         with:
           r-version: ${{ matrix.config.r }}
+          http-user-agent: ${{ matrix.config.http-user-agent }}
+          use-public-rspm: true
 
-      - uses: r-lib/actions/setup-pandoc@master
-
-      - name: Query dependencies
-        run: |
-          install.packages(c('remotes', 'zoo', 'sf'))
-          saveRDS(remotes::dev_package_deps(dependencies = TRUE), ".github/depends.Rds", version = 2)
-        shell: Rscript {0}
-
-      - name: Cache R packages
-        if: runner.os != 'Windows'
-        uses: actions/cache@v1
+      - uses: r-lib/actions/setup-r-dependencies@v1
         with:
-          path: ${{ env.R_LIBS_USER }}
-          key: ${{ runner.os }}-r-${{ matrix.config.r }}-1-${{ hashFiles('.github/depends.Rds') }}
-          restore-keys: ${{ runner.os }}-r-${{ matrix.config.r }}-1-
-
-      - name: Install system dependencies
-        if: runner.os == 'Linux'
-        env:
-          RHUB_PLATFORM: linux-x86_64-ubuntu-gcc
-        run: |
-          Rscript -e "remotes::install_github('r-hub/sysreqs')"
-          sysreqs=$(Rscript -e "cat(sysreqs::sysreq_commands('DESCRIPTION'))")
-          sudo -s eval "$sysreqs"
-
-      - name: mac dependencies
-        if: runner.os == 'macOS'
-        run: brew install pkg-config gdal proj geos udunits
-        
-      - name: Install dependencies
-        run: |
-          remotes::install_deps(dependencies = TRUE)
-          install.packages(c('remotes', 'zoo', 'sf'))
-          remotes::install_cran("rcmdcheck")
-        shell: Rscript {0}
-
-      - name: Session info
-        run: |
-          options(width = 100)
-          pkgs <- installed.packages()[, "Package"]
-          sessioninfo::session_info(pkgs, include_base = TRUE)
-        shell: Rscript {0}
+          extra-packages: rcmdcheck
 
-      - name: Check
-        env:
-          _R_CHECK_CRAN_INCOMING_: false
-        run: rcmdcheck::rcmdcheck(args = c("--no-manual", "--as-cran"), error_on = "warning", check_dir = "check")
-        shell: Rscript {0}
+      - uses: r-lib/actions/check-r-package@v1
 
       - name: Show testthat output
         if: always()
@@ -91,7 +52,7 @@ jobs:
 
       - name: Upload check results
         if: failure()
-        uses: actions/upload-artifact@master
+        uses: actions/upload-artifact@main
         with:
           name: ${{ runner.os }}-r${{ matrix.config.r }}-results
-          path: check
+          path: check
\ No newline at end of file