3. Subject to article 5 below, there shall on the appointed day be transferred to the employment of the Inner London Education Authority every person who is employed for the whole, or substantially the whole, of his time by an inner London borough at or for the purposes of a junior training centre or special care unit provided in pursuance of arrangements under section 12 of the Health Services and Public Health Act 1968 for training children classified under section 57 of the Education Act 1944 as unsuitable for education at school.