"We promised people we weren't going to do this." There is exasperation in the voice of a long time Labour adviser. But as every hour passes, it is more likely the UK will soon have its seventh prime minister in 10 years. Talk of Sir Keir Starmer fighting is fading, his exit seems more likely as the weekend goes on. The prime minister is at his country retreat, Chequers, spending time with his wife. The man coming for his job, Andy Burnham, is spending the weekend with his family, away from