That's pretty much common knowledge now but the OP says he is looking at a Premium account not Access and the LLU platform is not having the FUP enforced SFAIK - I did leave O2 a month ago for cable due to BT's incompetence in fixing a line fault.
I doubt if the OP is still looking!!!!
As I pointed out to the person who resurrected this thread for some incomprehensible reason, the question was 54 weeks ago.
Bob's broadband basic info/help site:
www.robertos.me.uk
ISP history: Demon dialup >> Freeserve dialup >> BT Broadband >> Prodigynet >> Newnet >> O2 Standard.
Domains,web and mail hosting history: Purple Cloud >>
Tsohost.