"That's why I'm so happy too," Alice chimes in. "School got out very early."

And please, why would she want to be at school when she can instead do something fun, like sit here and watch television with her mom? Of course she's going to be more cheery in this case than after spending a full day at school.

And.. well, she's also just glad to see Aziraphale here because it means that there's really nothing going on out there yet, despite all the warnings. The three of them are fine, just like usually. It's a relief.