“The present situation only ends one of two ways,” the normally-loyal Labour MP told HuffPost UK. “Either Rachel goes or Keir goes.”As Keir Starmer approaches his first anniversary as prime minister, the question of how much longer he can last is now being openly debated at Westminster.It is a remarkable turnaround, just 12 months after he led Labour to a landslide election victory which left him with a barely-believable 165-seat Commons majority.The events of the last month have led many of those MPs who were elected last July to reluctantly come to the conclusion that Starmer is not the man to lead them into the next election.“He should have three years to turn it around, but if he keeps going like this he won’t get those three years,” said one source.The PM has U-turned on no fewer than three occasions in the past month alone – on winter fuel payments, whether to hold a national inquiry into child grooming gangs and, in the last 24 hours, over cuts to the welfare budget.Labour MPs fear Starmer is now a prime minister who is buffeted by events rather than one who makes the political weather, and are demanding big changes to the way he goes about his business.“We were told to support taking winter fuel payments off millions of pensioners,