Continuity mistake: When Christopher Robin first appears in uniform he is wearing second lieutenant's pips. In the following scene, later the same day, they have disappeared, but he is still wearing an open-necked officer's battledress tunic with shirt and tie. He says he is a private. In fact, he joined the Royal Engineers as a sapper (not a private) and was later commissioned.
Factual error: The musicians in the (real) Band of the Coldstream Guards that plays Happy Birthday for Christopher Robin are wearing their 21st-century uniforms and medals.
Factual error: Christopher Robin and his schoolmates undergo the army medical (which he fails) at the outbreak of war. In fact, Christopher Robin had left school and was at Cambridge by the time the war broke out. In addition, those that pass the medical go off to war in privates' uniforms. As the school (Stowe) is a prestigious public school, almost all would have been commissioned and never served as privates.
