Like the anytime+ option. 
Will this affect sky broadband data allowance though? 
Are you on unlimited? As yes it will count to data useage.... each film is around 4Gb 
no, we've knocked It down to minimum on sky's service, as it's hopelessly slow as all isp's are on that line... we use 02 which is usable at 4meg and provided by her work. Not sure the allowance on 02, will have to check. 
Actually, that's arse backwards. Sky(nor any other isp) could not provide the promised speed. But where still charging the promised speed, of 2.5meg at the time, so we had to insist they dropped the bill in line with the service we where getting. If they up the package, and hence speed(?) the line fails to provide any service at all, as it seizes up with errors.
We might beable to use that to keep the bill down... Maybe. 
The advertised package should be described as
up to 8/24/40/76

Guessing this was a while ago, as O2 were one of the first to offer ADSL2 (courtesy of buying Be), which can provide better speeds on a given line than ADSL1. I'd bet BT have upgraded your exchange to be ADSL2+, so all providers should be able to provide similar (most providers use BT lines and equipment, O2, being LLU, just use BT lines, but their own exchange equipment).
In fact, I'd bet that most providers would offer a UP TO 76Mb circuit, as BT must have fibred your area. LLU providers are currently unable to offer this generally.