diff --git a/.github/workflows/lint_nagfor.yml b/.github/workflows/lint_nagfor.yml
index 305c8d7e11..826efcba50 100644
--- a/.github/workflows/lint_nagfor.yml
+++ b/.github/workflows/lint_nagfor.yml
@@ -38,7 +38,7 @@ jobs:
           export PATH=$PATH:"~/local/bin"
           source ~/local/bin/nag_licensing || (echo "\n\nNAG licensing failed.\n\n" && exit 2)
           cd "$ROOT_DIR"/fortran/${{ matrix.solver }}
-          if [[ $(($(echo $(date +%d) | sed 's|^0||') % 2)) == 0 ]] ; then
+          if [[ $(($(date +%-d) % 2)) == 0 ]] ; then
               bash ./flint -n --all
           else
               bash ./mlint -n --all
diff --git a/.github/workflows/stress_test_fortran.yml b/.github/workflows/stress_test_fortran.yml
index dbe3137be5..df081c53f5 100644
--- a/.github/workflows/stress_test_fortran.yml
+++ b/.github/workflows/stress_test_fortran.yml
@@ -84,7 +84,7 @@ jobs:
         run: |
           cd "$ROOT_DIR"/fortran/tests
           export TESTDIM=${{ matrix.testdim }}
-          RK=$((2**($(date +%d) % 3 + 2)))
+          RK=$((2**($(date +%-d) % 3 + 2)))
           echo "RK = " $RK
           if [[ $RK==16 && dfrv == *${{ matrix.compiler }}* ]] ; then
               echo "r16 test is skipped for compiler " ${{ matrix.compiler }}
diff --git a/.github/workflows/test_absoft.yml b/.github/workflows/test_absoft.yml
index 3afac8c580..aed922648b 100644
--- a/.github/workflows/test_absoft.yml
+++ b/.github/workflows/test_absoft.yml
@@ -38,7 +38,7 @@ jobs:
           source "$AFDIR"/bin/absvars.sh
           export LD_LIBRARY_PATH=/usr/lib/x86_64-linux-gnu/:$LD_LIBRARY_PATH
           # Use $(( )) rather than $(expr ). See https://unix.stackexchange.com/questions/63166/bash-e-exits-when-let-or-expr-evaluates-to-0
-          FFLAGS=-O$(($(date +%d) % 4))
+          FFLAGS=-O$(($(date +%-d) % 4))
           FFLAGS=${FFLAGS/O0/g}
           export FFLAGS
           cd "$ROOT_DIR"/fortran/tests && make atest_${{ matrix.ikind }}.${{ matrix.solver }}
diff --git a/.github/workflows/test_nagfor.yml b/.github/workflows/test_nagfor.yml
index 394df5fff7..5b82bf4187 100644
--- a/.github/workflows/test_nagfor.yml
+++ b/.github/workflows/test_nagfor.yml
@@ -38,7 +38,7 @@ jobs:
           export PATH=$PATH:"~/local/bin"
           source ~/local/bin/nag_licensing || echo "\n\nNAG licensing failed.\n\n"
           # Use $(( )) rather than $(expr ). See https://unix.stackexchange.com/questions/63166/bash-e-exits-when-let-or-expr-evaluates-to-0
-          FFLAGS=-O$(($(date +%d) % 5))
+          FFLAGS=-O$(($(date +%-d) % 5))
           FFLAGS=${FFLAGS/O0/g}
           FFLAGS=${FFLAGS/O4/fast}
           export FFLAGS