I guess these guys do have communication gaps. Got another mail from them (below), they changed my plan. I can see my line speed has gone to 10mbps on the modem but speedtest still gives me 512kbps. I should have hardly used 10-15 Gb this month.
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Bill plan for your airtel fixedline ID has been changed to Airtel-UL-Rapid New Plus 1099 40GB (8Mbps/512Kbps) COMBO Plan with effect from 04-Feb-2015.
Bill plan details are listed below:
High Speed Data Limit / FUP Limit: 40 GB.
Post FUP: Data speed will be revised as per your bill plan.
For any support, please feel free to write in to us at
121@in.airtel.com
EDIT------------
sent them a query mail for the speed and got another reply:
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As checked in our records, we would like to inform you that, the above mentioned account number is active under UL-Rapid New Plus 1099 40GB (8Mbps/512Kbps) COMBO Plan with effect from 04-02-2015. Your revised bandwidth of 08 Mbps would be provisioned within the next 24 hours.
We request you to reboot your modem after a period of 24 hours to replenish your revised quota and bandwidth. Tariff details for the activated bill plan is included for your reference.
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I guess it looks like a new plan by the name.