Virgin Media has published the download and upload traffic management constraints that will accompany the new "double" speeds as they roll out. Full details at thinkbroadband.com, but here are the XXL limitations:
XXL 50Mbps and XL60: If you download more than 5Gb between 4pm and 9pm your download speed will be halved for five hours, if you upload more than 12Gb you'll have to put up with operating at 25% of your normal speed for five hours. XXL 100Mbps customers hit their speed bumps at 10Gb on the download and 12Gb on the upload.
Now I'm not a heavy downloading demon so these won't affect me (half of 100mb will be the speed I currently enjoy and I don't need 100mb to be truthful) but many will be unhappy.
What makes me very unhappy at the moment is the unreliability of the broadband in South East London of late: up and down on a daily basis after years of stability and where once I had an impressive 48mbps I'm seeing speeds of half that. I'm told by CS that it's due to the engineering going on (we're due for the speed doubling in July) but the nightly loss of service is turning out to be a huge problem for my daughter's exam prep. Come on Virgin, sort it out please!