diff -r c51380879054 -r 23ed47a895d5 mercurial/hg.py
--- a/mercurial/hg.py	Sat Oct 14 15:42:38 2017 -0400
+++ b/mercurial/hg.py	Sat Oct 14 03:13:50 2017 -0400
@@ -757,7 +757,10 @@
     This returns whether conflict is detected at updating or not.
     """
     if updatecheck is None:
-        updatecheck = ui.config('experimental', 'updatecheck')
+        updatecheck = ui.config('commands', 'update.check')
+        if updatecheck is None:
+            # pre-4.4 compat on the old spelling of this config item
+            updatecheck = ui.config('experimental', 'updatecheck')
         if updatecheck not in ('abort', 'none', 'linear', 'noconflict'):
             # If not configured, or invalid value configured
             updatecheck = 'linear'