diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index bd856a0..4241153 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -108,7 +108,7 @@ rootfs:secure:
   script:
     - |
       REPRO_ARGS=""
-      if [ "$GROUP" = "repro" ]; then
+      if [[ "$GROUP" == "repro" ]]; then
         SOURCE_DATE_EPOCH=$(date -u -d "-1 day" +%s)
         REPRO_ARGS="--source-date-epoch=${SOURCE_DATE_EPOCH} --rewrite-timestamp"
       fi
diff --git a/scripts/make-dockerfile.sh b/scripts/make-dockerfile.sh
index 3404efc..aec8e97 100755
--- a/scripts/make-dockerfile.sh
+++ b/scripts/make-dockerfile.sh
@@ -14,7 +14,7 @@ BUILD_VERSION="${BUILD_VERSION:-dev}"
 CI_COMMIT_SHA="${CI_COMMIT_SHA:-$(git rev-parse HEAD)}"
 
 # Honor SOURCE_DATE_EPOCH for the repro GROUP
-if [ "$GROUP" = "repro" ]; then
+if [[ "$GROUP" == "repro" ]]; then
     CREATED_TIMESTAMP=$(date -u -d "@$SOURCE_DATE_EPOCH" +%Y-%m-%dT%H:%M:%SZ)
 else
     CREATED_TIMESTAMP=$(date -Is)