Did you have to supply proof of purchase when you sent it to the service center?
Sent from my LT30p using xda app-developers app
They asked me to, and I did. I don't know if I absolutely had to - I'm sure it was to help prove the warranty, but the warranty lasts for two years and the phone has only just been released for a year.. so it couldn't be out of warranty even if I wanted it to be!