slapos_accounting: Use same earlier start date when generate Aggregated Sale Packing List

master/bt5/slapos_accounting/SkinTemplateItem/portal_skins/slapos_accounting/OrderBuilder_generateSlapOSAggregatedMovementList.py

@@ -84,8 +84,8 @@ for movement in movement_list:
     if subscription is not None:
       temp_movement.edit(
           specialise=specialise_to_set,
-          causality=subscription)
-
+          causality=subscription,
+          start_date=movement.getStartDate())
   elif movement.getCausality(portal_type="Subscription Request") is not None:
     temp_movement.edit(
       specialise=specialise_to_set,

master/bt5/slapos_accounting/SkinTemplateItem/portal_skins/slapos_accounting/SalePackingList_postSlapOSAggregatedDeliveryBuilder.py

@@ -33,11 +33,19 @@ input_movement_list = [restrictedTraverse(q) for q in
     if restrictedTraverse(q).getDestination() == person and \
       restrictedTraverse(q).getSpecialise() in specialise_filter_list]
 
+min_start_date = None
 for delivery_line in input_movement_list:
   delivery_line.setGroupingReference(reference)
 
+  if min_start_date is None:
+    min_start_date = delivery_line.getStartDate()
+  elif delivery_line.getStartDate() < min_start_date:
+    min_start_date = delivery_line.getStartDate()
+
 if context.getCausalityState() == 'draft':
   context.startBuilding()
 
 if context.getStartDate() is None:
-  context.setStartDate(DateTime().earliestTime())
+  if min_start_date is None:
+    min_start_date = DateTime().earliestTime()
+  context.setStartDate(min_start_date)