Why did people appear to remember what was going on at the time they left England when they returned from Narnia?

Question

Very closely related: Why don't people in the Chronicles of Narnia have trouble "transitioning" back to their old life after extended times in other worlds?

When the Pevensies accidentally wandered back into England, they had been away for years (or perhaps even decades) and had only a vague recollection that they'd even seen the lamp-post before, which implied that they had forgotten. Why didn't they continue to express that kind of confusion when they got back? The book implies that they remember a good deal about what was going on when they left; for example, they remembered to apologize to the Professor for accidentally leaving the coats that they borrowed in Narnia.

The book also mentions that Mrs. Macready avoided the room. While I don't remember if it's explicitly stated in the text, I've always assumed that that implied that they remembered why they had entered the wardrobe in the first place (I could be wrong about that, though).

When they got back, did they remember "where they had left off" with their old life? Did they remember everything that they would have remembered when they left (e.g. what they had for lunch the day before they left, the fact that someone asked them to clean their room today, etc.)?

Similarly, after returning from Narnia in Prince Caspian, they apparently got on the train that they were planning on taking to begin with and carried on with their business. (Granted, their absence wasn't nearly as long that time).

While the texts admittedly don't talk a lot about their "ordinary" lives in England, there's no indication in the text as to their behavior being noticeably strange (with the exception of Lucy's return from the wardrobe). So, why did they remember as much as they did?

Answer 1

It was part of their 'resetting' back to life in our world.

Here's the dialogue from when the Pevensies discover the lamp-post again after spending years or decades ruling Narnia:

“I know not how it is, but this lamp on the post worketh upon me strangely. It runs in my mind that I have seen the like before; as it were in a dream, or in the dream of a dream.”

“Sir,” answered they all, “it is even so with us also.”

“And more,” said Queen Lucy, “for it will not go out of my mind that if we pass this post and lantern either we shall find strange adventures or else some great change of our fortunes.”

“Madam,” said King Edmund, “the like foreboding stirreth in my heart also.”

Note the archaic formalism of their speech; at this point they're still entirely within their lives as Narnian kings and queens. Some part of them still remembers the lamp-post, but it's buried deep, and their memories of their previous lives in our world presumably still deeper.

Then, a few paragraphs later, the really important part:

So these Kings and Queens entered the thicket, and before they had gone a score of paces they all remembered that the thing they had seen was called a lamppost, and before they had gone twenty more they noticed that they were making their way not through branches but through coats. And next moment they all came tumbling out of a wardrobe door into the empty room, and they were no longer Kings and Queens in their hunting array but just Peter, Susan, Edmund and Lucy in their old clothes.

The memory of the lamp-post returns to them, as if by magic. The hold of Narnia is weakening, and they're turning back to their old selves. The same magic which enables them to turn from adults back to children, and their clothes to turn from Narnian royal garb to English schoolkids' clothing, also returns their much-faded memories of our world into their heads. Thus it makes sense to conclude that along with big things like "what's a lamp-post" (which they'd also forgotten during their years in Narnia), small things like "what's for dinner" would also have returned to their memories by magic.

The quotes above are only from The Lion, the Witch, and the Wardrobe - the book spanning the longest period of Narnian time in which memories of our world might fade - but presumably the same happens in the other stories too (except The Horse and His Boy and The Last Battle, of course, which don't feature any return to our world). LWW was the original Narnia book, the first one Lewis wrote, so Lewis would have had this model in mind when writing the others.