We are running and unconstrained ASCP plan and have a requirement to have two lead-times for the sam

We are running an unconstrained ASCP plan and have a requirement to have two lead-times for the same Item/org and are not using ASL's or Supplier Calendars.  We simply place the long lead items Purchase Orders based on China capacity and want to see the planned orders where needed within the china lead-time.  So far I have been unable to not get it to create the natural time fence.  I want it to use the processing time on the item which is very short.  I have the firm Internal time fence as no.  Does anyone have a profile set-up for