Work Order Reprint intermittently moving WO status backwards

When running WO print/reprint, work order status is intermittently moving backwards from a 40 to a 15.  I've checked processing options on both the print and re-print and don't see any issue there.  Currently we are setup to attach parts list but not routings; we are not printing shortage or summarized parts list; parts list records are coded to backflush at completions.  90% of the time, the process works as desired, but the other 10% the R31410/R31415 is moving the status backwards.