Using EAM_PROCESS_WO_PUB.PROCESS_WO to update work order dates

I am trying to use the APPS package EAM_PROCESS_WO_PUB procedure PROCESS_WO() to update a work order's scheduled start and scheduled completion dates. So I created a work order record and filled in only the necessary info.

transaction_type := EAM_PROCESS_WO_PUB.G_OPR_UPDATE; 
wip_entity_id := 123456; 
organization_id := 123; 
scheduled_start_date := ?;
scheduled_completion_date : = ?;

Reading through some documentation I figured out that the work order needs to be in "Released" status. You should be able to just set the start or completion date since the resource usage will either back-date or forward-date the other scheduled date.