It's not legislation. The government just leaned on the larger ISPs. The smaller ISPs are ignoring the whole thing.
"Cameron gave the companies an October deadline to comply with the demands to filter the terms. He said that if the government is not satisfied with the progress it is prepared to take legislative action."
The democratic process is for new laws to be debated in the houses. Cameron circumvented this process quite deliberately.
These rarely become law and that one didn't have government support. Hague at the time said the gov opposed claire perry's "on by default" request.
Perhaps people are confused by that bill?