diff --git a/spec/lib/tasks/count_duplicates_spec.rb b/spec/lib/tasks/count_duplicates_spec.rb
index ba9aa7e59..9a733d029 100644
--- a/spec/lib/tasks/count_duplicates_spec.rb
+++ b/spec/lib/tasks/count_duplicates_spec.rb
@@ -44,7 +44,12 @@ RSpec.describe "count_duplicates" do
         end
 
         it "creates a csv with correct duplicate numbers" do
-          expect(storage_service).to receive(:write_file).with(/scheme-duplicates-.*\.csv/, "\uFEFFOrganisation id,Number of duplicate sets,Total duplicate schemes\n#{organisation.id},2,5\n#{organisation2.id},1,5\n")
+          expect(storage_service).to receive(:write_file).with(/scheme-duplicates-.*\.csv/, satisfy do |s|
+            s.start_with?("\uFEFFOrganisation id,Number of duplicate sets,Total duplicate schemes") &&
+              s.include?("#{organisation.id},2,5") &&
+              s.include?("#{organisation2.id},1,5") &&
+              s.count("\n") == 3
+          end)
           expect(Rails.logger).to receive(:info).with("Download URL: #{test_url}")
           task.invoke
         end