Continuity mistake: Chapter 14 The Hermit is describing the scene at the attack on the castle at Anvard, and how Rabadash's army is attempting to break the gates using a battering ram. As he relates what he sees to Aravis and the horses, he says, "They have learned something from the failure of last night's assault." The initial assault was actually a full day earlier and this was the second morning. In the previous chapter, Shasta rode all night, then slept 24 hours at the dwarves' before returning.
Continuity mistake: When Aravis and the Horses are at the Hermit's and Shasta is at Anvard, the three decide it is time to resume their journey to Narnia. Aravis says, "We must see Shasta first and say good-bye to him - and - and apologize." At this point they do know he is the king of Archenland's son and will be staying in Anvard. That is revealed later to them in the chapter. She should have said, "We need to go to Anvard and get Shasta and then go to Narnia."