Yes. Our experience in the U.K. is very different, and I think it partly reflects the way in which witness protection has evolved in a very ad hoc way, without any kind of legislative framework until relatively recently and with individual police forces really coming to their own arrangements. Certainly in the work I did in Scotland with the Strathclyde Police Witness Protection Programme, there was no formal appeals process, and witnesses felt acutely vulnerable. If things started going wrong, the only people they had immediate contact with were the officers looking after them. They had no direct line of communication to a senior investigating officer or anybody else, and they felt acutely vulnerable as a result. They had to make that relationship with their protecting officers work; otherwise, they would feel incredibly isolated.
Certainly when I was studying this particular protection program, there was no formal appeals process if people were threatened or were actually told to leave the program.