My position is under notice of redundancy but the boss's new wife is already sitting in my seat?

He admitted that he would be outsourcing secretarial services and that his wife would be helping out ... I thought once the position was redundant, it was redundant, at least for six months .... any comments would be helpful. Have spoken to ACAS and they agree that it is unfair dismissal but do I want to jeopardise my redundancy pay for something that is likely to happen anyway? I've been in the position for four years and have developed the role way beyond what it was originally advertised for.