Re CC wages - I read that pay slip etc as basic £21000, with allowances, £28000. Ie allowances of £7000. I agree the lack of a comma after 'with allowances' in the original text is confusing. So on 75% contract, after 20 years a full time basic is £28000, presumably allowances would be similarly increased to £9333. I don't know which bits of the allowances are taxable, it seems likely some may be, so grossing up isn't straightforward.