diff --git a/deploy/varnish/default.vcl.template b/deploy/varnish/default.vcl.template
index 55f284e..b9aa5bc 100644
--- a/deploy/varnish/default.vcl.template
+++ b/deploy/varnish/default.vcl.template
@@ -52,7 +52,8 @@ sub vcl_backend_response {
     set beresp.ttl = std.duration(regsub(beresp.http.Cache-Control, "(?i).*max-age=([0-9]+).*", "\1") + "s", 0s);
   } else if (beresp.http.Expires) {
     # fallback na Expires
-    set beresp.ttl = std.time(beresp.http.Expires, now, 0s) - now;
+    set beresp.ttl = std.time(beresp.http.Expires, now) - now;
+    if (beresp.ttl < 0s) { set beresp.ttl = 0s; }
   } else {
     # ostateczny fallback
     set beresp.ttl = 60s;