Quando Albus e Severus discutiram sobre destruir o Time-Turner, Albus sugeriu "stupefy", porque " eles foram originalmente destruídos usando Stupefy " (Parte 2, Ato 3, Cena 16)

Mas isso parece contradizer o cânone JKR , já que em HP & OotP, o feitiço Stupefy não destruiu os Time-Turners. Nem sequer os atingiu - atingiu e destruiu o case onde eles estavam armazenados; e isso faz com que todo o estoque fique preso em um ciclo infinito:

Harry flung himself sideways as Neville took aim again and shouted, “STUPEFY !”
The jet of red light flew right over the Death Eater’s shoulder and hit a glass-fronted cabinet on the wall full of variously shaped hourglasses.
The cabinet fell to the floor and burst apart, glass flying everywhere, then sprang back up onto the wall, fully mended, then fell down again, and shattered —

...

Harry stuck his head out of the door and looked around cautiously. The baby-headed Death Eater was screaming and banging into things, toppling grandfather clocks and overturning desks, bawling and confused, while the glass cabinet that Harry now suspected had contained Time-Turners continued to fall, shatter, and repair itself on the wall behind them.

(OotP, CHAPTER THIRTY-FIVE - "BEYOND THE VEIL")

É claro, esse tipo de coisa já foi contradito um pouco em Half-Blood Prince , mas o ponto principal (eles foram destruídos, não destruídos por "Stupefy") é:

“We couldn’t have done,” said Hermione. “We smashed the entire stock of Ministry Time-Turners when we were there last summer. It was in the Daily Prophet.” (H-BP, CHAPTER ELEVEN - "HERMIONE’S HELPING HAND")

Então, por que eles sugerem usar "Stupefy"? Eles estavam intimamente familiarizados com os eventos da história original e os detalhes eram abertamente conhecidos.