CWPS scheme has a Normal Retirement Age of 65, it would be highly unlikely that they would let him retire early. As the pension fund is small he will be able to take the benefits as a "Trivial Pension" which means that he will be able to take part of it as a tax free lump sum with the remainder as taxable cash. The level of tax that he will pay will depend on his tax credits, tax bands, other income etc. so would not be able to answer that part of your question.