You receive a hero's welcome in Britain. Everyone is happy that peace has been achieved. You proudly hold up the paper that Hitler had signed.
As you stand there happily receiving praise that you have successfully averted war, you feel profoundly grateful to have stopped Hitler's territorial ambitions.
When you return to your office, a spy brings in a History textbook from the future which had somehow been teleported into England. The book appears to have been printed in 2024. When you flip through its pages, you turn pale with shock...