1984 PolyGram CD Matrix and Mother/Stamper Question

I currently have 2 PolyGram CDs that are nearly identical.

Charles Dutoit
Montreal Symphony Orchestra
Falla, The Three Cornered Hat & El Amor Brujo
London 410 008-2 LH
London blue red ring by PolyGram silverfacehub
Made in W. Germany by PolyGram (label)
Barcode: 028941000828
Matrix and mother/stamper codes: 410 008-2 01 DS ZA​

Both CDs have the same Matrix (the glass master id and the mother/stamper codes "410 008-2 01 DS ZA".

The glass master id "410 008-2 01" and "DS" portion of the mother/stamper code are located in identical position in the matrix (mirror) band on BOTH CDs, however the "ZA" portion of the mother/stamper code is located in a different position along the matrix (mirror band). If you look at the matrix and mother/stamper codes radially, the "ZA" differs in location by 30 degrees between the two CDs,

I've always interpreted the mother/stamper code "DS ZA" as being part of the stamping process and occurring at the same time in manufacturing . It seems from this example, the matrix and mother/stamper codes are generated in three steps.

Does anyone have any ideas or perhaps knowledge/expertise as to the manufacturing process for early CDs at PolyGram that can account for the difference?