Client has employees who are having approval rights. However, they are not assigning approval limits against primary positions, but they call with some other name like approval level 1, approval level2.
So as a solution, we created new positions as "approval level1" , "approval level2" and assigned to employees as their seconda.ry assignments.
Then we created approval hierarchy with these secondary positions.
However, when we went to po creation, and go for forward-to for approval, we saw that seconddary assignment based person's name were not in list.
Reason was that oracle itself only consider primary assignments in approval list generation. See this thread Position Hierarchy Based on secondary assignments.