diff --git a/src/scripts/deploy_ecs_scheduled_task.sh b/src/scripts/deploy_ecs_scheduled_task.sh
index a00efb8..fc0a946 100644
--- a/src/scripts/deploy_ecs_scheduled_task.sh
+++ b/src/scripts/deploy_ecs_scheduled_task.sh
@@ -8,7 +8,7 @@ fi
 
 ORB_STR_RULE_NAME="$(circleci env subst "${ORB_STR_RULE_NAME}")"
 
-if [[ -n $ORB_STR_RULE_NAME ]]; then
+if [ -z "$ORB_STR_RULE_NAME" ]; then
     echo "To deploy with an scheduled task, you must provide a rule name"
     exit 1
 fi