Index: app/models/issue_relation.rb
===================================================================
--- app/models/issue_relation.rb	(revision 2670)
+++ app/models/issue_relation.rb	(working copy)
@@ -72,7 +72,7 @@
   
   def successor_soonest_start
     return nil unless (TYPE_PRECEDES == self.relation_type) && (issue_from.start_date || issue_from.due_date)
-    (issue_from.due_date || issue_from.start_date) + 1 + delay
+    (issue_from.due_date || issue_from.start_date) + delay
   end
   
   def <=>(relation)