employee.line manager level

Hi,

  I'm trying to write a workflow that traverses the managerial hierarchy to find suitable approvers in the chain'o'command.  I believe I should be able to use the employee.line manager level field to stop looking up the hierarchy once it gets a certain number of level up then return one or all of the people found.  What I'm finding is that no matter what value I put in for employee line manager level I always only manage to get the immediate supervisor returned.  For instance I get the same result whether the condition is line manager level >= 1 or line manager level >= 10. 

I'm using AX 2012 CU3.  Any ideas on what I'm doing wrong?

Thanks

David