cannot change managerial approval

 on 12.06 and as of this week we cannot successfully change managerial approval on submission of a iprocurement req.  We can select the new approver but when we click on SUBMIT the hierarchy does not change.  If the users exists ebs and then goes back in they can successfully change the approval hierachy.  This is not an issue if you insert a user and was not an issue prior to the last few days   What changed we moved to a new linux server