How can job data be setup so that only the current active job title (ER1) is displayed when ER0 is a

When an employee’s primary assignment ER0 is suspended & that suspended home position shares the same job code as the new active assignment ER1 (the employee is fulfilling a similar role with the same grade & type of function elsewhere in the University; Thus, their job codes are deemed the same). the same Job Title appears in the drop down list when an employee attempts to Request an Absence (see attachment).  This is confusing for the employee because the employee does not know which row to select for their current active assignment.

How can job data be setup so that only the current active job title (ER1) is displayed?  Currently the job data is setup like this: