Fixed a regression (dropped auto_now for update). Also use timezone.now
instead of datetime.now
diff --git a/xos/core/models/plcorebase.py b/xos/core/models/plcorebase.py
index 76c2e54..6be949d 100644
--- a/xos/core/models/plcorebase.py
+++ b/xos/core/models/plcorebase.py
@@ -199,7 +199,7 @@
     # default values for created and updated are only there to keep evolution
     # from failing.
     created = models.DateTimeField(auto_now_add=True)
-    updated = models.DateTimeField(auto_now=True)
+    updated = models.DateTimeField(default=timezone.now)
     enacted = models.DateTimeField(null=True, blank=True, default=None)
     policed = models.DateTimeField(null=True, blank=True, default=None)
 
@@ -272,7 +272,7 @@
                     ignore_composite_key_check=False
 
         if 'synchronizer' not in threading.current_thread().name:
-            self.updated = datetime.datetime.now()
+            self.updated = timezone.now()
 
         super(PlCoreBase, self).save(*args, **kwargs)