on a serious note ( not quuting the superman comments ) i belive the 300gb fup was lifted on the 1st april, so in an answer to your question, as much as you like m8.
Why tell me? 
Better to click the Reply button on the post you are replying to.
according to roumours and then people on the bt forums, the fup has been lifted as of 1 april, it has been rumoured for a while, as bt state that only 0.5% of their users get anywhere near tis usage, people on the bt forums state that they have phone bt india for their usage stats and have been told there is no longer any fup profile.
just going off what i have read on the bt user forums.