Just a random thought - it would be interesting to be able to support random serial number generation.  It seems this would be trivial to implement IF the current system that replaces JLCJLCJLCJLCwith the "internal production number" is an automated software-driven process.  If this was under software control, it seems that it should be able to replace something like S#S#S#S#0000 with an auto-incrementing 4 digit serial number starting at 0, or replace S#S#S#S#25123 with an auto-incrementing 5-digit serial number starting at 25123.

Other formats could possibly be supported just by customizing the placeholder.