update preffix, in order to avoid pkg conflicts on pool
diff --git a/aptly/server/mirror/debian/aptly.yml b/aptly/server/mirror/debian/aptly.yml
index e919b20..48a176e 100644
--- a/aptly/server/mirror/debian/aptly.yml
+++ b/aptly/server/mirror/debian/aptly.yml
@@ -12,5 +12,5 @@
           publisher:
             component: extra
             distributions:
-              - nightly/trusty
-              - nightly/xenial
+              - trusty/nightly
+              - xenial/nightly