diff --git a/src/modules/first-leg/api/customs.test.mjs b/src/modules/first-leg/api/customs.test.mjs
index 2e780ee..778d96d 100644
--- a/src/modules/first-leg/api/customs.test.mjs
+++ b/src/modules/first-leg/api/customs.test.mjs
@@ -22,7 +22,7 @@ test('sends multi-inbound scope, optimistic versions and idempotency for every w
   assert.match(source, /params\.append\('inboundIds', id\)/)
   assert.match(source, /expectedVersion: document\.source\.version/)
   assert.match(source, /params: \{ expectedVersion: document\.source\.version \}/)
-  assert.equal(source.match(/'Idempotency-Key'/g)?.length, 4)
+  assert.equal(source.match(/'Idempotency-Key'/g)?.length, 6)
   assert.match(source, /data\.append\('file', file\)/)
   assert.match(source, /file\.size > MAX_CUSTOMS_FILE_SIZE/)
 })