I'm sorry to repeat myself, but, this is quite typical of Government interference which caused it in the first place. After it's implemented they are having to look at ways to resolve the problem 'they' created. It's very much the same as the silly cookie law we were challenged with.
Correct consultation at the outset would have seen this coming.
The government is drawing up a list of sites inadvertently blocked by the filters it asked internet service providers (ISPs) to implement.
Many sites on the list are run by charities that aim to educate children and others about health, sex education and drugs issues.
The whitelist will be used to ensure the sites are not immediately blocked.
The list has emerged from a working group looking into accidental blocking and how to fix the problem. 'Master list'
@engine, what will happen is that ISPs will not worry too much about false positives because "innocent sites can go on the white-list", so they will then use very aggressive filtering. At that point the white list will be a necessity.