I want to know the answer to the following question:
What kind of school did Thatcher end the compulsion for existing schools to convert to?
All the background I'm provided with is that "She ended the compulsion on local authorities to convert, however, many local authorities were so far down the path that it would have been prohibitively expensive to attempt to reverse the process, and more comprehensive schools were established under Mrs Thatcher than any other education secretary.". Is that enough to answer the question?