If it's the same part number this makes sense.All the standard Leon Cupra wheels are ET50
Leon Sub8 Wheels are ET50
Leon Performance pack wheels ET50
Leon Carbon Edition wheels are ET50
However:
Leon Cupra R ST wheels are ET45 (Copper)
Ateca Cupra wheels are ET45 (Copper)
Leon Cupra R (5 door) wheels are ET40 (copper)
They're the same wheel.someone with the Cupra R ST posted a picture of the back of them, its the same part number unless I'm being dyslexic (which is a slight possibility).
Edit:
@KernelOkey do you still have the picture of the rear of your standard R ST wheels?
I was told by my local seat dealer the part number was different and they wouldn't give me the part number for the R ST. No-one has confirmed the R ST part number to me so I only had my SEAT dealer's word to go on.