Free Speed Upgrade For Prepaid Customers

Tata Indicom
I had taken Surf 6000 256kbps prepaid plan this year just for trying out Tata broadband with 6000mb/year. Now this automatically got upgraded to 12000mb/year and 2mbps for free!
I still don't know why tata did this but all prepaid volume based customers have been upgraded to 2mbps in Pune for free and data limit has been doubled.
Has anyone else seen such a rise in speed with their Tata Indicom prepaid connections? Rs.4041 for 12GB/year and 2mbps speed is a good bargain for those who don't use too much! The cost works out to 30 paise per MB at 2mbps whereas earlier it was 66 paise per MB at 256kbps.See my speed results below. I still don't believe it.