diff -r 4c5035111f5f trytond/trytond/modules/stock/move.py
--- a/trytond/trytond/modules/stock/move.py	Thu Sep 14 17:48:18 2017 +0200
+++ b/trytond/trytond/modules/stock/move.py	Fri Sep 15 09:19:22 2017 +0200
@@ -1,6 +1,7 @@
 # This file is part of Tryton.  The COPYRIGHT file at the top level of
 # this repository contains the full copyright notices and license terms.
 import datetime
+import hashlib
 import operator
 from decimal import Decimal
 from functools import partial
@@ -189,11 +190,13 @@
                 | Eval('shipment'))
             }, depends=['state', 'shipment'],
         select=True)
-    effective_date = fields.Date("Effective Date", readonly=True, select=True,
+    effective_date = fields.Date("Effective Date", select=True,
         states={
             'required': Eval('state') == 'done',
+            'readonly': (Eval('state').in_(['cancel', 'done'])
+                | Eval('shipment')),
             },
-        depends=['state'])
+        depends=['state', 'shipment'])
     state = fields.Selection([
         ('staging', 'Staging'),
         ('draft', 'Draft'),
@@ -737,12 +740,18 @@
             types = cls.check_origin_types()
         if not types:
             return
-        for move in moves:
-            if ((move.from_location.type in types
-                        or move.to_location.type in types)
-                    and not move.origin):
-                cls.raise_user_warning('%s.done' % move,
-                    'no_origin', move.rec_name)
+
+        def no_origin(move):
+            return ((move.from_location.type in types) ^
+                (move.to_location.type in types)
+                and not move.origin)
+        moves = filter(no_origin, moves)
+        if moves:
+            names = ', '.join(m.rec_name for m in moves[:5])
+            if len(moves) > 5:
+                names += '...'
+            warning_name = '%s.done' % hashlib.md5(str(moves)).hexdigest()
+            cls.raise_user_warning(warning_name, 'no_origin', names)

     def pick_product(self, location_quantities):
         """