I suspect that it is a typo...one too many zeroes. Most anthropologists put the start of homo sapiens at between 120,000 to 500,000 years ago (I know, big window). So either this axe belonged to an earlier hominid or those sapiens characters jumped from East Africa to the midlands much more promptly than anyone has guessed before. If I am right that there is one too many zeroes, that puts it at 50,000 years old, which coincides nicely with the begining of the early upper paleolithic era...which certainly seems to fit the design of the axe...and it would fit the migratory models.
Most Anthropolgist think Homo sapiens originated around 100,000 years ago in Africa. They guestimate its appearance in Europe about 40,000 years ago.
At 500,000 years ago your probably looking at an Homo antecessor or Homo heidelbergensis, predecessors of Homo neanderthalensis or H. sapiens neanderthalensis, depending on the authority.
Homos erectus goes back to more than ONE million years with previous findings in England dating back to 750,000 years ago.