I originally preordered on the 10th July in the UK, all was good until they started appearing in my local stores on the 17th, with at least a week more to wait I decided to cancel.
I went through calling support to try and cancel my nexus 7, they said I couldn't as the process had already begun, I then emailed support through Google wallet and advised that I wanted to cancel my order as no payment had been taken and it wasn't planned on being despatched until the following week (18th July)
At this point I bought my Nexus 7 from my local PC world (19th July) even though I had had no response from Google. To be safe I logged onto Google wallet and removed my card details, when I removed my card a message popped up on screen saying this would effect my nexus 16gb order so I figured my order would eventually cancel due to no payment.
Today (23rd July) my available balance on my bank account was reduced by roughly ?208 so Google was still able to charge my card. I called my bank and managed to get the payment reversed, and the bank advised me to cancel my card as they said Google would just attempt to take the payment again tomorrow, so now I am without my bank card for a week.
So it took some work but I think (hopefully) I've beaten Google into submission and my order will now inevitably be cancelled.
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