Method Directive modification without messing up existing functionality

I need to slightly modify the functionality of BO.ReceiptsFromMfg and Method OnChangeActTranQty so that it ignores a certain job type (i.e. prototype jobs).
The actual method was determined by using the TraceData log function as it displays the error message “The quantity entered exceeds the quantity completed for this job”. We need this check to be ignored on prototype jobs but I’m not sure how to accomplish that without overwriting the existing functionality of the BO Method’s Base Processing.
Any ideas would be most welcome.
Thank you,

Simply set the returned value (in Post Processing) to blank when your condition is met.
Then, no message, nothing stopped.