The cable operator announced in January that its 4m customers would have their speeds doubled at no extra cost in a network upgrade programme funded by a £110m cash injection using the "remaining proceeds" from its £339m sale of the 50% stake in pay-TV operator UKTV last year.
Over the next 18 months, subscribers to Virgin Media's current 10Mbps, 20Mbps, 30Mbps and 50Mbps services will see their speeds "at least doubled", while the company's 100Mbps package will increase to a market-leading 120Mbps.
By mid-2013, the network upgrade will have rolled out across Virgin Media's entire footprint of nearly 13 million homes in Britain.
Virgin has now started upgrading the first batch of 1.5 million homes as part of the "double speeds" programme. Over March and April, the following areas will be upgraded: Newcastle, Tilbury, Southend, Ely, Melton, Andover, Poplar, Dover, Ashford, Rawtenstall, Belfast, Solihull, Maidstone, Castlecary, Grimsby, Ipswich, St Mellons, Flitwick, Preston, Dundee, Glenrothes, Wakefield, Doncaster, Barnsley, Cambridge, Cosham, Hemel Hempstead, Mansfield, Oldham and Bedford.
Customers will have their speeds doubled automatically as the rollout reaches their area, and they can check when they will be upgraded by visiting the 'double speed' section of Virgin Media's website.
Virgin Media also said that when the 120Mbps service rolls out, subscribers will also see a "price drop" to the high-end package.
"Virgin Media has driven broadband development in the UK and we're delighted to be boosting our customers' broadband speeds once again," said Jon James, the executive director of broadband at Virgin Media.
"Following our Double Speeds programme, all of our customers will be 'superfast' as standard and ready to access a new breed of high bandwidth entertainment services.
"By continuing to give our customers faster speeds and greater value services, we're committed to providing our customers the best broadband in the UK."
As with most internet service providers, Virgin Media operates traffic management across its network to manage the network capacity and quality at peak times.
The company said that it will introduce new peak time allowances for customers as part of the speed-doubling programme, and it will be trialling a "variety of different approaches" to traffic management over the coming months to make the system "more intelligent and flexible".
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