Apologies if there is already a thread on this, but I can't recall seeing anything.
My current Clubby is on a lease rather than PCP so outside the scope of claims but I had a Polo GTi about 6 years ago. I've therefore followed Martin Lewis's advice and sent VW an email to see if they might pay some compensation for overcharging. Nothing ventured, nothing gained and I'm not expecting anything.
I'll consider any repayment a bonus and the email took literally 15 minutes including digging out the finance agreement.
Fingers crossed.