diff --git a/README.md b/README.md
index e878699..79d2780 100644
--- a/README.md
+++ b/README.md
@@ -44,5 +44,5 @@ certbot certonly --manual --email you@example.com \
 </pre>
 
 Please note that NameSilo DNS propagation takes up to **15 minutes**,
-so the scripts will wait 16 minutes before completing.
+so the scripts will wait 20 minutes before completing.
 
diff --git a/authenticator.py b/authenticator.py
index 30d88e6..01fbe7a 100644
--- a/authenticator.py
+++ b/authenticator.py
@@ -1,8 +1,8 @@
-#!/usr/bin/env python3.7
+#!/usr/bin/env python3.8
 
 #  authenticator.py
 #
-#  Copyright (c) 2019, Erik C. Thauvin (erik@thauvin.net)
+#  Copyright (c) 2019-20, Erik C. Thauvin (erik@thauvin.net)
 #  All rights reserved.
 #
 #  Redistribution and use in source and binary forms, with or without
@@ -39,7 +39,15 @@ import urllib.request
 
 import untangle
 
-from config import apikey
+from config import apikey, wait
+
+
+def sleep(minutes):
+    if minutes < 16:
+        minutes = 16
+    print("Waiting", minutes, "minutes for DNS changes to complete...")
+    time.sleep(minutes * 60)
+
 
 domain = os.environ['CERTBOT_DOMAIN']
 validation = os.environ['CERTBOT_VALIDATION']
@@ -79,5 +87,5 @@ else:
                                xml.namesilo.reply.code.cdata), file=sys.stderr)
     sys.exit(1)
 
-# Sleep 16 minutes
-time.sleep(960)
+# Sleep X minutes
+sleep(wait)
diff --git a/cleanup.py b/cleanup.py
index 27d38c4..eb9a289 100644
--- a/cleanup.py
+++ b/cleanup.py
@@ -2,7 +2,7 @@
 
 #  cleanup.py
 #
-#  Copyright (c) 2019, Erik C. Thauvin (erik@thauvin.net)
+#  Copyright (c) 2019-20, Erik C. Thauvin (erik@thauvin.net)
 #  All rights reserved.
 #
 #  Redistribution and use in source and binary forms, with or without
diff --git a/config.py b/config.py
index b30c1c3..8679450 100644
--- a/config.py
+++ b/config.py
@@ -1,2 +1,4 @@
 # Get your API Key from: https://www.namesilo.com/account_api.php
 apikey = "YOUR_API_KEY"
+# Minutes to wait for DNS changes to complete.
+wait = 20