diff --git a/app/views/application/app.html.erb b/app/views/application/app.html.erb
index e02cb3f0a..db302df40 100644
--- a/app/views/application/app.html.erb
+++ b/app/views/application/app.html.erb
@@ -30,7 +30,7 @@
 
     <script>
       window._default_sync_server = "<%= ENV['SF_DEFAULT_SERVER'] %>";
-      window._next_version_sync_server = "<%= ENV['SF_NEXT_VERSION_SERVER'] %>";
+      window._next_version_sync_server = "<%= ENV['SF_NEXT_VERSION_SERVER'] || ENV['SF_DEFAULT_SERVER'] %>";
       window._extensions_manager_location = "<%= ENV['EXTENSIONS_MANAGER_LOCATION'] %>";
       window._batch_manager_location = "<%= ENV['BATCH_MANAGER_LOCATION'] %>";
       window._bugsnag_api_key = "<%= ENV['BUGSNAG_API_KEY'] %>";
diff --git a/index.html b/index.html
index 1c0798bc1..a7cfd5561 100644
--- a/index.html
+++ b/index.html
@@ -30,7 +30,7 @@
 
 <body
   data-default-sync-server="<%= env.DEV_DEFAULT_SYNC_SERVER %>"
-  data-next-version-sync-server="<%= env.DEV_NEXT_VERSION_SYNC_SERVER %>"
+  data-next-version-sync-server="<%= env.DEV_NEXT_VERSION_SYNC_SERVER || env.DEV_DEFAULT_SYNC_SERVER %>"
   data-extensions-manager-location="<%= env.DEV_EXTENSIONS_MANAGER_LOCATION %>"
   data-bugsnag-api-key="<%= env.DEV_BUGSNAG_API_KEY %>"
 >
