How to use alternate item structure in Unconstrainted Supply Plans

Summary:

A CPG customer has a semifinished FG, which is manufactured in house as well as using a contract manufacture. We are using unconstrained planning. A basic solution is to choose alternate item structure and work definition during releasing the planned orders for the FG item.

But the question is how does the planner decide which planned orders should be released with primary item structure and alternate item structures. We are suggesting to maintain this outside Oracle as it is part of S& OP process. Customer should manage this information outside Oracle and use it while releasing the planned orders for FG. But wanted inputs if there could be any better solution.