The chip was made with the H&C mold.
Molds have different numbers of cavaties. Some Have 4, 8, etc.
The number of cavaties in a mold is how many chips are stamped out at the same time.

IMO your chip and the others in the cavaties at that time got hit twice. There will be others like it.
I have seen other chips that were hit twice. Not a real rare error.
If I'm wrong maybe Blanchard will come along and correct me.

IMO it is not the type error that should have a different TCR number but The authors will make that decision.