Limiting Completions according to WO Status

Hi all

There is a need to limit WO completions until a WO is at or past a certain status.  In the processing options for P31114 there is an option to set a WO status after which shop floor activity CANNOT be entered, but I can't see any for setting a WO status below which shop floor activity CANNOT be entered.  A client has a need for this as the factory is performing completions to WO's that do not have a parts list and routing attached and as such no backflushing of raw material is being done.  This has a detrimental effect